mergerfs/libfuse/lib/fmt/core.h

3324 lines
109 KiB
C++

// Formatting library for C++ - the core API for char/UTF-8
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.
#ifndef FMT_CORE_H_
#define FMT_CORE_H_
#include <cstddef> // std::byte
#include <cstdio> // std::FILE
#include <cstring> // std::strlen
#include <iterator>
#include <limits>
#include <string>
#include <type_traits>
// The fmt library version in the form major * 10000 + minor * 100 + patch.
#define FMT_VERSION 90100
#if defined(__clang__) && !defined(__ibmxl__)
# define FMT_CLANG_VERSION (__clang_major__ * 100 + __clang_minor__)
#else
# define FMT_CLANG_VERSION 0
#endif
#if defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER) && \
!defined(__NVCOMPILER)
# define FMT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
#else
# define FMT_GCC_VERSION 0
#endif
#ifndef FMT_GCC_PRAGMA
// Workaround _Pragma bug https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59884.
# if FMT_GCC_VERSION >= 504
# define FMT_GCC_PRAGMA(arg) _Pragma(arg)
# else
# define FMT_GCC_PRAGMA(arg)
# endif
#endif
#ifdef __ICL
# define FMT_ICC_VERSION __ICL
#elif defined(__INTEL_COMPILER)
# define FMT_ICC_VERSION __INTEL_COMPILER
#else
# define FMT_ICC_VERSION 0
#endif
#ifdef _MSC_VER
# define FMT_MSC_VERSION _MSC_VER
# define FMT_MSC_WARNING(...) __pragma(warning(__VA_ARGS__))
#else
# define FMT_MSC_VERSION 0
# define FMT_MSC_WARNING(...)
#endif
#ifdef _MSVC_LANG
# define FMT_CPLUSPLUS _MSVC_LANG
#else
# define FMT_CPLUSPLUS __cplusplus
#endif
#ifdef __has_feature
# define FMT_HAS_FEATURE(x) __has_feature(x)
#else
# define FMT_HAS_FEATURE(x) 0
#endif
#if (defined(__has_include) || FMT_ICC_VERSION >= 1600 || \
FMT_MSC_VERSION > 1900) && \
!defined(__INTELLISENSE__)
# define FMT_HAS_INCLUDE(x) __has_include(x)
#else
# define FMT_HAS_INCLUDE(x) 0
#endif
#ifdef __has_cpp_attribute
# define FMT_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
#else
# define FMT_HAS_CPP_ATTRIBUTE(x) 0
#endif
#define FMT_HAS_CPP14_ATTRIBUTE(attribute) \
(FMT_CPLUSPLUS >= 201402L && FMT_HAS_CPP_ATTRIBUTE(attribute))
#define FMT_HAS_CPP17_ATTRIBUTE(attribute) \
(FMT_CPLUSPLUS >= 201703L && FMT_HAS_CPP_ATTRIBUTE(attribute))
// Check if relaxed C++14 constexpr is supported.
// GCC doesn't allow throw in constexpr until version 6 (bug 67371).
#ifndef FMT_USE_CONSTEXPR
# if (FMT_HAS_FEATURE(cxx_relaxed_constexpr) || FMT_MSC_VERSION >= 1912 || \
(FMT_GCC_VERSION >= 600 && FMT_CPLUSPLUS >= 201402L)) && \
!FMT_ICC_VERSION && !defined(__NVCC__)
# define FMT_USE_CONSTEXPR 1
# else
# define FMT_USE_CONSTEXPR 0
# endif
#endif
#if FMT_USE_CONSTEXPR
# define FMT_CONSTEXPR constexpr
#else
# define FMT_CONSTEXPR
#endif
#if ((FMT_CPLUSPLUS >= 202002L) && \
(!defined(_GLIBCXX_RELEASE) || _GLIBCXX_RELEASE > 9)) || \
(FMT_CPLUSPLUS >= 201709L && FMT_GCC_VERSION >= 1002)
# define FMT_CONSTEXPR20 constexpr
#else
# define FMT_CONSTEXPR20
#endif
// Check if constexpr std::char_traits<>::{compare,length} are supported.
#if defined(__GLIBCXX__)
# if FMT_CPLUSPLUS >= 201703L && defined(_GLIBCXX_RELEASE) && \
_GLIBCXX_RELEASE >= 7 // GCC 7+ libstdc++ has _GLIBCXX_RELEASE.
# define FMT_CONSTEXPR_CHAR_TRAITS constexpr
# endif
#elif defined(_LIBCPP_VERSION) && FMT_CPLUSPLUS >= 201703L && \
_LIBCPP_VERSION >= 4000
# define FMT_CONSTEXPR_CHAR_TRAITS constexpr
#elif FMT_MSC_VERSION >= 1914 && FMT_CPLUSPLUS >= 201703L
# define FMT_CONSTEXPR_CHAR_TRAITS constexpr
#endif
#ifndef FMT_CONSTEXPR_CHAR_TRAITS
# define FMT_CONSTEXPR_CHAR_TRAITS
#endif
// Check if exceptions are disabled.
#ifndef FMT_EXCEPTIONS
# if (defined(__GNUC__) && !defined(__EXCEPTIONS)) || \
(FMT_MSC_VERSION && !_HAS_EXCEPTIONS)
# define FMT_EXCEPTIONS 0
# else
# define FMT_EXCEPTIONS 1
# endif
#endif
#ifndef FMT_DEPRECATED
# if FMT_HAS_CPP14_ATTRIBUTE(deprecated) || FMT_MSC_VERSION >= 1900
# define FMT_DEPRECATED [[deprecated]]
# else
# if (defined(__GNUC__) && !defined(__LCC__)) || defined(__clang__)
# define FMT_DEPRECATED __attribute__((deprecated))
# elif FMT_MSC_VERSION
# define FMT_DEPRECATED __declspec(deprecated)
# else
# define FMT_DEPRECATED /* deprecated */
# endif
# endif
#endif
// [[noreturn]] is disabled on MSVC and NVCC because of bogus unreachable code
// warnings.
#if FMT_EXCEPTIONS && FMT_HAS_CPP_ATTRIBUTE(noreturn) && !FMT_MSC_VERSION && \
!defined(__NVCC__)
# define FMT_NORETURN [[noreturn]]
#else
# define FMT_NORETURN
#endif
#if FMT_HAS_CPP17_ATTRIBUTE(fallthrough)
# define FMT_FALLTHROUGH [[fallthrough]]
#elif defined(__clang__)
# define FMT_FALLTHROUGH [[clang::fallthrough]]
#elif FMT_GCC_VERSION >= 700 && \
(!defined(__EDG_VERSION__) || __EDG_VERSION__ >= 520)
# define FMT_FALLTHROUGH [[gnu::fallthrough]]
#else
# define FMT_FALLTHROUGH
#endif
#ifndef FMT_NODISCARD
# if FMT_HAS_CPP17_ATTRIBUTE(nodiscard)
# define FMT_NODISCARD [[nodiscard]]
# else
# define FMT_NODISCARD
# endif
#endif
#ifndef FMT_USE_FLOAT
# define FMT_USE_FLOAT 1
#endif
#ifndef FMT_USE_DOUBLE
# define FMT_USE_DOUBLE 1
#endif
#ifndef FMT_USE_LONG_DOUBLE
# define FMT_USE_LONG_DOUBLE 1
#endif
#ifndef FMT_INLINE
# if FMT_GCC_VERSION || FMT_CLANG_VERSION
# define FMT_INLINE inline __attribute__((always_inline))
# else
# define FMT_INLINE inline
# endif
#endif
// An inline std::forward replacement.
#define FMT_FORWARD(...) static_cast<decltype(__VA_ARGS__)&&>(__VA_ARGS__)
#ifdef _MSC_VER
# define FMT_UNCHECKED_ITERATOR(It) \
using _Unchecked_type = It // Mark iterator as checked.
#else
# define FMT_UNCHECKED_ITERATOR(It) using unchecked_type = It
#endif
#ifndef FMT_BEGIN_NAMESPACE
# define FMT_BEGIN_NAMESPACE \
namespace fmt { \
inline namespace v9 {
# define FMT_END_NAMESPACE \
} \
}
#endif
#ifndef FMT_MODULE_EXPORT
# define FMT_MODULE_EXPORT
# define FMT_MODULE_EXPORT_BEGIN
# define FMT_MODULE_EXPORT_END
# define FMT_BEGIN_DETAIL_NAMESPACE namespace detail {
# define FMT_END_DETAIL_NAMESPACE }
#endif
#if !defined(FMT_HEADER_ONLY) && defined(_WIN32)
# define FMT_CLASS_API FMT_MSC_WARNING(suppress : 4275)
# ifdef FMT_EXPORT
# define FMT_API __declspec(dllexport)
# elif defined(FMT_SHARED)
# define FMT_API __declspec(dllimport)
# endif
#else
# define FMT_CLASS_API
# if defined(FMT_EXPORT) || defined(FMT_SHARED)
# if defined(__GNUC__) || defined(__clang__)
# define FMT_API __attribute__((visibility("default")))
# endif
# endif
#endif
#ifndef FMT_API
# define FMT_API
#endif
// libc++ supports string_view in pre-c++17.
#if FMT_HAS_INCLUDE(<string_view>) && \
(FMT_CPLUSPLUS >= 201703L || defined(_LIBCPP_VERSION))
# include <string_view>
# define FMT_USE_STRING_VIEW
#elif FMT_HAS_INCLUDE("experimental/string_view") && FMT_CPLUSPLUS >= 201402L
# include <experimental/string_view>
# define FMT_USE_EXPERIMENTAL_STRING_VIEW
#endif
#ifndef FMT_UNICODE
# define FMT_UNICODE !FMT_MSC_VERSION
#endif
#ifndef FMT_CONSTEVAL
# if ((FMT_GCC_VERSION >= 1000 || FMT_CLANG_VERSION >= 1101) && \
FMT_CPLUSPLUS >= 202002L && !defined(__apple_build_version__)) || \
(defined(__cpp_consteval) && \
(!FMT_MSC_VERSION || _MSC_FULL_VER >= 193030704))
// consteval is broken in MSVC before VS2022 and Apple clang 13.
# define FMT_CONSTEVAL consteval
# define FMT_HAS_CONSTEVAL
# else
# define FMT_CONSTEVAL
# endif
#endif
#ifndef FMT_USE_NONTYPE_TEMPLATE_ARGS
# if defined(__cpp_nontype_template_args) && \
((FMT_GCC_VERSION >= 903 && FMT_CPLUSPLUS >= 201709L) || \
__cpp_nontype_template_args >= 201911L) && \
!defined(__NVCOMPILER)
# define FMT_USE_NONTYPE_TEMPLATE_ARGS 1
# else
# define FMT_USE_NONTYPE_TEMPLATE_ARGS 0
# endif
#endif
// Enable minimal optimizations for more compact code in debug mode.
FMT_GCC_PRAGMA("GCC push_options")
#if !defined(__OPTIMIZE__) && !defined(__NVCOMPILER)
FMT_GCC_PRAGMA("GCC optimize(\"Og\")")
#endif
FMT_BEGIN_NAMESPACE
FMT_MODULE_EXPORT_BEGIN
// Implementations of enable_if_t and other metafunctions for older systems.
template <bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
template <bool B, typename T, typename F>
using conditional_t = typename std::conditional<B, T, F>::type;
template <bool B> using bool_constant = std::integral_constant<bool, B>;
template <typename T>
using remove_reference_t = typename std::remove_reference<T>::type;
template <typename T>
using remove_const_t = typename std::remove_const<T>::type;
template <typename T>
using remove_cvref_t = typename std::remove_cv<remove_reference_t<T>>::type;
template <typename T> struct type_identity { using type = T; };
template <typename T> using type_identity_t = typename type_identity<T>::type;
template <typename T>
using underlying_t = typename std::underlying_type<T>::type;
template <typename...> struct disjunction : std::false_type {};
template <typename P> struct disjunction<P> : P {};
template <typename P1, typename... Pn>
struct disjunction<P1, Pn...>
: conditional_t<bool(P1::value), P1, disjunction<Pn...>> {};
template <typename...> struct conjunction : std::true_type {};
template <typename P> struct conjunction<P> : P {};
template <typename P1, typename... Pn>
struct conjunction<P1, Pn...>
: conditional_t<bool(P1::value), conjunction<Pn...>, P1> {};
struct monostate {
constexpr monostate() {}
};
// An enable_if helper to be used in template parameters which results in much
// shorter symbols: https://godbolt.org/z/sWw4vP. Extra parentheses are needed
// to workaround a bug in MSVC 2019 (see #1140 and #1186).
#ifdef FMT_DOC
# define FMT_ENABLE_IF(...)
#else
# define FMT_ENABLE_IF(...) enable_if_t<(__VA_ARGS__), int> = 0
#endif
FMT_BEGIN_DETAIL_NAMESPACE
// Suppresses "unused variable" warnings with the method described in
// https://herbsutter.com/2009/10/18/mailbag-shutting-up-compiler-warnings/.
// (void)var does not work on many Intel compilers.
template <typename... T> FMT_CONSTEXPR void ignore_unused(const T&...) {}
constexpr FMT_INLINE auto is_constant_evaluated(
bool default_value = false) noexcept -> bool {
#ifdef __cpp_lib_is_constant_evaluated
ignore_unused(default_value);
return std::is_constant_evaluated();
#else
return default_value;
#endif
}
// Suppresses "conditional expression is constant" warnings.
template <typename T> constexpr FMT_INLINE auto const_check(T value) -> T {
return value;
}
FMT_NORETURN FMT_API void assert_fail(const char* file, int line,
const char* message);
#ifndef FMT_ASSERT
# ifdef NDEBUG
// FMT_ASSERT is not empty to avoid -Wempty-body.
# define FMT_ASSERT(condition, message) \
::fmt::detail::ignore_unused((condition), (message))
# else
# define FMT_ASSERT(condition, message) \
((condition) /* void() fails with -Winvalid-constexpr on clang 4.0.1 */ \
? (void)0 \
: ::fmt::detail::assert_fail(__FILE__, __LINE__, (message)))
# endif
#endif
#if defined(FMT_USE_STRING_VIEW)
template <typename Char> using std_string_view = std::basic_string_view<Char>;
#elif defined(FMT_USE_EXPERIMENTAL_STRING_VIEW)
template <typename Char>
using std_string_view = std::experimental::basic_string_view<Char>;
#else
template <typename T> struct std_string_view {};
#endif
#ifdef FMT_USE_INT128
// Do nothing.
#elif defined(__SIZEOF_INT128__) && !defined(__NVCC__) && \
!(FMT_CLANG_VERSION && FMT_MSC_VERSION)
# define FMT_USE_INT128 1
using int128_opt = __int128_t; // An optional native 128-bit integer.
using uint128_opt = __uint128_t;
template <typename T> inline auto convert_for_visit(T value) -> T {
return value;
}
#else
# define FMT_USE_INT128 0
#endif
#if !FMT_USE_INT128
enum class int128_opt {};
enum class uint128_opt {};
// Reduce template instantiations.
template <typename T> auto convert_for_visit(T) -> monostate { return {}; }
#endif
// Casts a nonnegative integer to unsigned.
template <typename Int>
FMT_CONSTEXPR auto to_unsigned(Int value) ->
typename std::make_unsigned<Int>::type {
FMT_ASSERT(std::is_unsigned<Int>::value || value >= 0, "negative value");
return static_cast<typename std::make_unsigned<Int>::type>(value);
}
FMT_MSC_WARNING(suppress : 4566) constexpr unsigned char micro[] = "\u00B5";
constexpr auto is_utf8() -> bool {
// Avoid buggy sign extensions in MSVC's constant evaluation mode (#2297).
using uchar = unsigned char;
return FMT_UNICODE || (sizeof(micro) == 3 && uchar(micro[0]) == 0xC2 &&
uchar(micro[1]) == 0xB5);
}
FMT_END_DETAIL_NAMESPACE
/**
An implementation of ``std::basic_string_view`` for pre-C++17. It provides a
subset of the API. ``fmt::basic_string_view`` is used for format strings even
if ``std::string_view`` is available to prevent issues when a library is
compiled with a different ``-std`` option than the client code (which is not
recommended).
*/
template <typename Char> class basic_string_view {
private:
const Char* data_;
size_t size_;
public:
using value_type = Char;
using iterator = const Char*;
constexpr basic_string_view() noexcept : data_(nullptr), size_(0) {}
/** Constructs a string reference object from a C string and a size. */
constexpr basic_string_view(const Char* s, size_t count) noexcept
: data_(s), size_(count) {}
/**
\rst
Constructs a string reference object from a C string computing
the size with ``std::char_traits<Char>::length``.
\endrst
*/
FMT_CONSTEXPR_CHAR_TRAITS
FMT_INLINE
basic_string_view(const Char* s)
: data_(s),
size_(detail::const_check(std::is_same<Char, char>::value &&
!detail::is_constant_evaluated(true))
? std::strlen(reinterpret_cast<const char*>(s))
: std::char_traits<Char>::length(s)) {}
/** Constructs a string reference from a ``std::basic_string`` object. */
template <typename Traits, typename Alloc>
FMT_CONSTEXPR basic_string_view(
const std::basic_string<Char, Traits, Alloc>& s) noexcept
: data_(s.data()), size_(s.size()) {}
template <typename S, FMT_ENABLE_IF(std::is_same<
S, detail::std_string_view<Char>>::value)>
FMT_CONSTEXPR basic_string_view(S s) noexcept
: data_(s.data()), size_(s.size()) {}
/** Returns a pointer to the string data. */
constexpr auto data() const noexcept -> const Char* { return data_; }
/** Returns the string size. */
constexpr auto size() const noexcept -> size_t { return size_; }
constexpr auto begin() const noexcept -> iterator { return data_; }
constexpr auto end() const noexcept -> iterator { return data_ + size_; }
constexpr auto operator[](size_t pos) const noexcept -> const Char& {
return data_[pos];
}
FMT_CONSTEXPR void remove_prefix(size_t n) noexcept {
data_ += n;
size_ -= n;
}
// Lexicographically compare this string reference to other.
FMT_CONSTEXPR_CHAR_TRAITS auto compare(basic_string_view other) const -> int {
size_t str_size = size_ < other.size_ ? size_ : other.size_;
int result = std::char_traits<Char>::compare(data_, other.data_, str_size);
if (result == 0)
result = size_ == other.size_ ? 0 : (size_ < other.size_ ? -1 : 1);
return result;
}
FMT_CONSTEXPR_CHAR_TRAITS friend auto operator==(basic_string_view lhs,
basic_string_view rhs)
-> bool {
return lhs.compare(rhs) == 0;
}
friend auto operator!=(basic_string_view lhs, basic_string_view rhs) -> bool {
return lhs.compare(rhs) != 0;
}
friend auto operator<(basic_string_view lhs, basic_string_view rhs) -> bool {
return lhs.compare(rhs) < 0;
}
friend auto operator<=(basic_string_view lhs, basic_string_view rhs) -> bool {
return lhs.compare(rhs) <= 0;
}
friend auto operator>(basic_string_view lhs, basic_string_view rhs) -> bool {
return lhs.compare(rhs) > 0;
}
friend auto operator>=(basic_string_view lhs, basic_string_view rhs) -> bool {
return lhs.compare(rhs) >= 0;
}
};
using string_view = basic_string_view<char>;
/** Specifies if ``T`` is a character type. Can be specialized by users. */
template <typename T> struct is_char : std::false_type {};
template <> struct is_char<char> : std::true_type {};
FMT_BEGIN_DETAIL_NAMESPACE
// A base class for compile-time strings.
struct compile_string {};
template <typename S>
struct is_compile_string : std::is_base_of<compile_string, S> {};
// Returns a string view of `s`.
template <typename Char, FMT_ENABLE_IF(is_char<Char>::value)>
FMT_INLINE auto to_string_view(const Char* s) -> basic_string_view<Char> {
return s;
}
template <typename Char, typename Traits, typename Alloc>
inline auto to_string_view(const std::basic_string<Char, Traits, Alloc>& s)
-> basic_string_view<Char> {
return s;
}
template <typename Char>
constexpr auto to_string_view(basic_string_view<Char> s)
-> basic_string_view<Char> {
return s;
}
template <typename Char,
FMT_ENABLE_IF(!std::is_empty<std_string_view<Char>>::value)>
inline auto to_string_view(std_string_view<Char> s) -> basic_string_view<Char> {
return s;
}
template <typename S, FMT_ENABLE_IF(is_compile_string<S>::value)>
constexpr auto to_string_view(const S& s)
-> basic_string_view<typename S::char_type> {
return basic_string_view<typename S::char_type>(s);
}
void to_string_view(...);
// Specifies whether S is a string type convertible to fmt::basic_string_view.
// It should be a constexpr function but MSVC 2017 fails to compile it in
// enable_if and MSVC 2015 fails to compile it as an alias template.
// ADL invocation of to_string_view is DEPRECATED!
template <typename S>
struct is_string : std::is_class<decltype(to_string_view(std::declval<S>()))> {
};
template <typename S, typename = void> struct char_t_impl {};
template <typename S> struct char_t_impl<S, enable_if_t<is_string<S>::value>> {
using result = decltype(to_string_view(std::declval<S>()));
using type = typename result::value_type;
};
enum class type {
none_type,
// Integer types should go first,
int_type,
uint_type,
long_long_type,
ulong_long_type,
int128_type,
uint128_type,
bool_type,
char_type,
last_integer_type = char_type,
// followed by floating-point types.
float_type,
double_type,
long_double_type,
last_numeric_type = long_double_type,
cstring_type,
string_type,
pointer_type,
custom_type
};
// Maps core type T to the corresponding type enum constant.
template <typename T, typename Char>
struct type_constant : std::integral_constant<type, type::custom_type> {};
#define FMT_TYPE_CONSTANT(Type, constant) \
template <typename Char> \
struct type_constant<Type, Char> \
: std::integral_constant<type, type::constant> {}
FMT_TYPE_CONSTANT(int, int_type);
FMT_TYPE_CONSTANT(unsigned, uint_type);
FMT_TYPE_CONSTANT(long long, long_long_type);
FMT_TYPE_CONSTANT(unsigned long long, ulong_long_type);
FMT_TYPE_CONSTANT(int128_opt, int128_type);
FMT_TYPE_CONSTANT(uint128_opt, uint128_type);
FMT_TYPE_CONSTANT(bool, bool_type);
FMT_TYPE_CONSTANT(Char, char_type);
FMT_TYPE_CONSTANT(float, float_type);
FMT_TYPE_CONSTANT(double, double_type);
FMT_TYPE_CONSTANT(long double, long_double_type);
FMT_TYPE_CONSTANT(const Char*, cstring_type);
FMT_TYPE_CONSTANT(basic_string_view<Char>, string_type);
FMT_TYPE_CONSTANT(const void*, pointer_type);
constexpr bool is_integral_type(type t) {
return t > type::none_type && t <= type::last_integer_type;
}
constexpr bool is_arithmetic_type(type t) {
return t > type::none_type && t <= type::last_numeric_type;
}
FMT_NORETURN FMT_API void throw_format_error(const char* message);
struct error_handler {
constexpr error_handler() = default;
constexpr error_handler(const error_handler&) = default;
// This function is intentionally not constexpr to give a compile-time error.
FMT_NORETURN void on_error(const char* message) {
throw_format_error(message);
}
};
FMT_END_DETAIL_NAMESPACE
/** String's character type. */
template <typename S> using char_t = typename detail::char_t_impl<S>::type;
/**
\rst
Parsing context consisting of a format string range being parsed and an
argument counter for automatic indexing.
You can use the ``format_parse_context`` type alias for ``char`` instead.
\endrst
*/
template <typename Char, typename ErrorHandler = detail::error_handler>
class basic_format_parse_context : private ErrorHandler {
private:
basic_string_view<Char> format_str_;
int next_arg_id_;
FMT_CONSTEXPR void do_check_arg_id(int id);
public:
using char_type = Char;
using iterator = typename basic_string_view<Char>::iterator;
explicit constexpr basic_format_parse_context(
basic_string_view<Char> format_str, ErrorHandler eh = {},
int next_arg_id = 0)
: ErrorHandler(eh), format_str_(format_str), next_arg_id_(next_arg_id) {}
/**
Returns an iterator to the beginning of the format string range being
parsed.
*/
constexpr auto begin() const noexcept -> iterator {
return format_str_.begin();
}
/**
Returns an iterator past the end of the format string range being parsed.
*/
constexpr auto end() const noexcept -> iterator { return format_str_.end(); }
/** Advances the begin iterator to ``it``. */
FMT_CONSTEXPR void advance_to(iterator it) {
format_str_.remove_prefix(detail::to_unsigned(it - begin()));
}
/**
Reports an error if using the manual argument indexing; otherwise returns
the next argument index and switches to the automatic indexing.
*/
FMT_CONSTEXPR auto next_arg_id() -> int {
if (next_arg_id_ < 0) {
on_error("cannot switch from manual to automatic argument indexing");
return 0;
}
int id = next_arg_id_++;
do_check_arg_id(id);
return id;
}
/**
Reports an error if using the automatic argument indexing; otherwise
switches to the manual indexing.
*/
FMT_CONSTEXPR void check_arg_id(int id) {
if (next_arg_id_ > 0) {
on_error("cannot switch from automatic to manual argument indexing");
return;
}
next_arg_id_ = -1;
do_check_arg_id(id);
}
FMT_CONSTEXPR void check_arg_id(basic_string_view<Char>) {}
FMT_CONSTEXPR void check_dynamic_spec(int arg_id);
FMT_CONSTEXPR void on_error(const char* message) {
ErrorHandler::on_error(message);
}
constexpr auto error_handler() const -> ErrorHandler { return *this; }
};
using format_parse_context = basic_format_parse_context<char>;
FMT_BEGIN_DETAIL_NAMESPACE
// A parse context with extra data used only in compile-time checks.
template <typename Char, typename ErrorHandler = detail::error_handler>
class compile_parse_context
: public basic_format_parse_context<Char, ErrorHandler> {
private:
int num_args_;
const type* types_;
using base = basic_format_parse_context<Char, ErrorHandler>;
public:
explicit FMT_CONSTEXPR compile_parse_context(
basic_string_view<Char> format_str, int num_args, const type* types,
ErrorHandler eh = {}, int next_arg_id = 0)
: base(format_str, eh, next_arg_id), num_args_(num_args), types_(types) {}
constexpr auto num_args() const -> int { return num_args_; }
constexpr auto arg_type(int id) const -> type { return types_[id]; }
FMT_CONSTEXPR auto next_arg_id() -> int {
int id = base::next_arg_id();
if (id >= num_args_) this->on_error("argument not found");
return id;
}
FMT_CONSTEXPR void check_arg_id(int id) {
base::check_arg_id(id);
if (id >= num_args_) this->on_error("argument not found");
}
using base::check_arg_id;
FMT_CONSTEXPR void check_dynamic_spec(int arg_id) {
if (arg_id < num_args_ && types_ && !is_integral_type(types_[arg_id]))
this->on_error("width/precision is not integer");
}
};
FMT_END_DETAIL_NAMESPACE
template <typename Char, typename ErrorHandler>
FMT_CONSTEXPR void
basic_format_parse_context<Char, ErrorHandler>::do_check_arg_id(int id) {
// Argument id is only checked at compile-time during parsing because
// formatting has its own validation.
if (detail::is_constant_evaluated() && FMT_GCC_VERSION >= 1200) {
using context = detail::compile_parse_context<Char, ErrorHandler>;
if (id >= static_cast<context*>(this)->num_args())
on_error("argument not found");
}
}
template <typename Char, typename ErrorHandler>
FMT_CONSTEXPR void
basic_format_parse_context<Char, ErrorHandler>::check_dynamic_spec(int arg_id) {
if (detail::is_constant_evaluated()) {
using context = detail::compile_parse_context<Char, ErrorHandler>;
static_cast<context*>(this)->check_dynamic_spec(arg_id);
}
}
template <typename Context> class basic_format_arg;
template <typename Context> class basic_format_args;
template <typename Context> class dynamic_format_arg_store;
// A formatter for objects of type T.
template <typename T, typename Char = char, typename Enable = void>
struct formatter {
// A deleted default constructor indicates a disabled formatter.
formatter() = delete;
};
// Specifies if T has an enabled formatter specialization. A type can be
// formattable even if it doesn't have a formatter e.g. via a conversion.
template <typename T, typename Context>
using has_formatter =
std::is_constructible<typename Context::template formatter_type<T>>;
// Checks whether T is a container with contiguous storage.
template <typename T> struct is_contiguous : std::false_type {};
template <typename Char>
struct is_contiguous<std::basic_string<Char>> : std::true_type {};
class appender;
FMT_BEGIN_DETAIL_NAMESPACE
template <typename Context, typename T>
constexpr auto has_const_formatter_impl(T*)
-> decltype(typename Context::template formatter_type<T>().format(
std::declval<const T&>(), std::declval<Context&>()),
true) {
return true;
}
template <typename Context>
constexpr auto has_const_formatter_impl(...) -> bool {
return false;
}
template <typename T, typename Context>
constexpr auto has_const_formatter() -> bool {
return has_const_formatter_impl<Context>(static_cast<T*>(nullptr));
}
// Extracts a reference to the container from back_insert_iterator.
template <typename Container>
inline auto get_container(std::back_insert_iterator<Container> it)
-> Container& {
using base = std::back_insert_iterator<Container>;
struct accessor : base {
accessor(base b) : base(b) {}
using base::container;
};
return *accessor(it).container;
}
template <typename Char, typename InputIt, typename OutputIt>
FMT_CONSTEXPR auto copy_str(InputIt begin, InputIt end, OutputIt out)
-> OutputIt {
while (begin != end) *out++ = static_cast<Char>(*begin++);
return out;
}
template <typename Char, typename T, typename U,
FMT_ENABLE_IF(
std::is_same<remove_const_t<T>, U>::value&& is_char<U>::value)>
FMT_CONSTEXPR auto copy_str(T* begin, T* end, U* out) -> U* {
if (is_constant_evaluated()) return copy_str<Char, T*, U*>(begin, end, out);
auto size = to_unsigned(end - begin);
memcpy(out, begin, size * sizeof(U));
return out + size;
}
/**
\rst
A contiguous memory buffer with an optional growing ability. It is an internal
class and shouldn't be used directly, only via `~fmt::basic_memory_buffer`.
\endrst
*/
template <typename T> class buffer {
private:
T* ptr_;
size_t size_;
size_t capacity_;
protected:
// Don't initialize ptr_ since it is not accessed to save a few cycles.
FMT_MSC_WARNING(suppress : 26495)
buffer(size_t sz) noexcept : size_(sz), capacity_(sz) {}
FMT_CONSTEXPR20 buffer(T* p = nullptr, size_t sz = 0, size_t cap = 0) noexcept
: ptr_(p), size_(sz), capacity_(cap) {}
FMT_CONSTEXPR20 ~buffer() = default;
buffer(buffer&&) = default;
/** Sets the buffer data and capacity. */
FMT_CONSTEXPR void set(T* buf_data, size_t buf_capacity) noexcept {
ptr_ = buf_data;
capacity_ = buf_capacity;
}
/** Increases the buffer capacity to hold at least *capacity* elements. */
virtual FMT_CONSTEXPR20 void grow(size_t capacity) = 0;
public:
using value_type = T;
using const_reference = const T&;
buffer(const buffer&) = delete;
void operator=(const buffer&) = delete;
auto begin() noexcept -> T* { return ptr_; }
auto end() noexcept -> T* { return ptr_ + size_; }
auto begin() const noexcept -> const T* { return ptr_; }
auto end() const noexcept -> const T* { return ptr_ + size_; }
/** Returns the size of this buffer. */
constexpr auto size() const noexcept -> size_t { return size_; }
/** Returns the capacity of this buffer. */
constexpr auto capacity() const noexcept -> size_t { return capacity_; }
/** Returns a pointer to the buffer data. */
FMT_CONSTEXPR auto data() noexcept -> T* { return ptr_; }
/** Returns a pointer to the buffer data. */
FMT_CONSTEXPR auto data() const noexcept -> const T* { return ptr_; }
/** Clears this buffer. */
void clear() { size_ = 0; }
// Tries resizing the buffer to contain *count* elements. If T is a POD type
// the new elements may not be initialized.
FMT_CONSTEXPR20 void try_resize(size_t count) {
try_reserve(count);
size_ = count <= capacity_ ? count : capacity_;
}
// Tries increasing the buffer capacity to *new_capacity*. It can increase the
// capacity by a smaller amount than requested but guarantees there is space
// for at least one additional element either by increasing the capacity or by
// flushing the buffer if it is full.
FMT_CONSTEXPR20 void try_reserve(size_t new_capacity) {
if (new_capacity > capacity_) grow(new_capacity);
}
FMT_CONSTEXPR20 void push_back(const T& value) {
try_reserve(size_ + 1);
ptr_[size_++] = value;
}
/** Appends data to the end of the buffer. */
template <typename U> void append(const U* begin, const U* end);
template <typename Idx> FMT_CONSTEXPR auto operator[](Idx index) -> T& {
return ptr_[index];
}
template <typename Idx>
FMT_CONSTEXPR auto operator[](Idx index) const -> const T& {
return ptr_[index];
}
};
struct buffer_traits {
explicit buffer_traits(size_t) {}
auto count() const -> size_t { return 0; }
auto limit(size_t size) -> size_t { return size; }
};
class fixed_buffer_traits {
private:
size_t count_ = 0;
size_t limit_;
public:
explicit fixed_buffer_traits(size_t limit) : limit_(limit) {}
auto count() const -> size_t { return count_; }
auto limit(size_t size) -> size_t {
size_t n = limit_ > count_ ? limit_ - count_ : 0;
count_ += size;
return size < n ? size : n;
}
};
// A buffer that writes to an output iterator when flushed.
template <typename OutputIt, typename T, typename Traits = buffer_traits>
class iterator_buffer final : public Traits, public buffer<T> {
private:
OutputIt out_;
enum { buffer_size = 256 };
T data_[buffer_size];
protected:
FMT_CONSTEXPR20 void grow(size_t) override {
if (this->size() == buffer_size) flush();
}
void flush() {
auto size = this->size();
this->clear();
out_ = copy_str<T>(data_, data_ + this->limit(size), out_);
}
public:
explicit iterator_buffer(OutputIt out, size_t n = buffer_size)
: Traits(n), buffer<T>(data_, 0, buffer_size), out_(out) {}
iterator_buffer(iterator_buffer&& other)
: Traits(other), buffer<T>(data_, 0, buffer_size), out_(other.out_) {}
~iterator_buffer() { flush(); }
auto out() -> OutputIt {
flush();
return out_;
}
auto count() const -> size_t { return Traits::count() + this->size(); }
};
template <typename T>
class iterator_buffer<T*, T, fixed_buffer_traits> final
: public fixed_buffer_traits,
public buffer<T> {
private:
T* out_;
enum { buffer_size = 256 };
T data_[buffer_size];
protected:
FMT_CONSTEXPR20 void grow(size_t) override {
if (this->size() == this->capacity()) flush();
}
void flush() {
size_t n = this->limit(this->size());
if (this->data() == out_) {
out_ += n;
this->set(data_, buffer_size);
}
this->clear();
}
public:
explicit iterator_buffer(T* out, size_t n = buffer_size)
: fixed_buffer_traits(n), buffer<T>(out, 0, n), out_(out) {}
iterator_buffer(iterator_buffer&& other)
: fixed_buffer_traits(other),
buffer<T>(std::move(other)),
out_(other.out_) {
if (this->data() != out_) {
this->set(data_, buffer_size);
this->clear();
}
}
~iterator_buffer() { flush(); }
auto out() -> T* {
flush();
return out_;
}
auto count() const -> size_t {
return fixed_buffer_traits::count() + this->size();
}
};
template <typename T> class iterator_buffer<T*, T> final : public buffer<T> {
protected:
FMT_CONSTEXPR20 void grow(size_t) override {}
public:
explicit iterator_buffer(T* out, size_t = 0) : buffer<T>(out, 0, ~size_t()) {}
auto out() -> T* { return &*this->end(); }
};
// A buffer that writes to a container with the contiguous storage.
template <typename Container>
class iterator_buffer<std::back_insert_iterator<Container>,
enable_if_t<is_contiguous<Container>::value,
typename Container::value_type>>
final : public buffer<typename Container::value_type> {
private:
Container& container_;
protected:
FMT_CONSTEXPR20 void grow(size_t capacity) override {
container_.resize(capacity);
this->set(&container_[0], capacity);
}
public:
explicit iterator_buffer(Container& c)
: buffer<typename Container::value_type>(c.size()), container_(c) {}
explicit iterator_buffer(std::back_insert_iterator<Container> out, size_t = 0)
: iterator_buffer(get_container(out)) {}
auto out() -> std::back_insert_iterator<Container> {
return std::back_inserter(container_);
}
};
// A buffer that counts the number of code units written discarding the output.
template <typename T = char> class counting_buffer final : public buffer<T> {
private:
enum { buffer_size = 256 };
T data_[buffer_size];
size_t count_ = 0;
protected:
FMT_CONSTEXPR20 void grow(size_t) override {
if (this->size() != buffer_size) return;
count_ += this->size();
this->clear();
}
public:
counting_buffer() : buffer<T>(data_, 0, buffer_size) {}
auto count() -> size_t { return count_ + this->size(); }
};
template <typename T>
using buffer_appender = conditional_t<std::is_same<T, char>::value, appender,
std::back_insert_iterator<buffer<T>>>;
// Maps an output iterator to a buffer.
template <typename T, typename OutputIt>
auto get_buffer(OutputIt out) -> iterator_buffer<OutputIt, T> {
return iterator_buffer<OutputIt, T>(out);
}
template <typename Buffer>
auto get_iterator(Buffer& buf) -> decltype(buf.out()) {
return buf.out();
}
template <typename T> auto get_iterator(buffer<T>& buf) -> buffer_appender<T> {
return buffer_appender<T>(buf);
}
template <typename T, typename Char = char, typename Enable = void>
struct fallback_formatter {
fallback_formatter() = delete;
};
// Specifies if T has an enabled fallback_formatter specialization.
template <typename T, typename Char>
using has_fallback_formatter =
#ifdef FMT_DEPRECATED_OSTREAM
std::is_constructible<fallback_formatter<T, Char>>;
#else
std::false_type;
#endif
struct view {};
template <typename Char, typename T> struct named_arg : view {
const Char* name;
const T& value;
named_arg(const Char* n, const T& v) : name(n), value(v) {}
};
template <typename Char> struct named_arg_info {
const Char* name;
int id;
};
template <typename T, typename Char, size_t NUM_ARGS, size_t NUM_NAMED_ARGS>
struct arg_data {
// args_[0].named_args points to named_args_ to avoid bloating format_args.
// +1 to workaround a bug in gcc 7.5 that causes duplicated-branches warning.
T args_[1 + (NUM_ARGS != 0 ? NUM_ARGS : +1)];
named_arg_info<Char> named_args_[NUM_NAMED_ARGS];
template <typename... U>
arg_data(const U&... init) : args_{T(named_args_, NUM_NAMED_ARGS), init...} {}
arg_data(const arg_data& other) = delete;
auto args() const -> const T* { return args_ + 1; }
auto named_args() -> named_arg_info<Char>* { return named_args_; }
};
template <typename T, typename Char, size_t NUM_ARGS>
struct arg_data<T, Char, NUM_ARGS, 0> {
// +1 to workaround a bug in gcc 7.5 that causes duplicated-branches warning.
T args_[NUM_ARGS != 0 ? NUM_ARGS : +1];
template <typename... U>
FMT_CONSTEXPR FMT_INLINE arg_data(const U&... init) : args_{init...} {}
FMT_CONSTEXPR FMT_INLINE auto args() const -> const T* { return args_; }
FMT_CONSTEXPR FMT_INLINE auto named_args() -> std::nullptr_t {
return nullptr;
}
};
template <typename Char>
inline void init_named_args(named_arg_info<Char>*, int, int) {}
template <typename T> struct is_named_arg : std::false_type {};
template <typename T> struct is_statically_named_arg : std::false_type {};
template <typename T, typename Char>
struct is_named_arg<named_arg<Char, T>> : std::true_type {};
template <typename Char, typename T, typename... Tail,
FMT_ENABLE_IF(!is_named_arg<T>::value)>
void init_named_args(named_arg_info<Char>* named_args, int arg_count,
int named_arg_count, const T&, const Tail&... args) {
init_named_args(named_args, arg_count + 1, named_arg_count, args...);
}
template <typename Char, typename T, typename... Tail,
FMT_ENABLE_IF(is_named_arg<T>::value)>
void init_named_args(named_arg_info<Char>* named_args, int arg_count,
int named_arg_count, const T& arg, const Tail&... args) {
named_args[named_arg_count++] = {arg.name, arg_count};
init_named_args(named_args, arg_count + 1, named_arg_count, args...);
}
template <typename... Args>
FMT_CONSTEXPR FMT_INLINE void init_named_args(std::nullptr_t, int, int,
const Args&...) {}
template <bool B = false> constexpr auto count() -> size_t { return B ? 1 : 0; }
template <bool B1, bool B2, bool... Tail> constexpr auto count() -> size_t {
return (B1 ? 1 : 0) + count<B2, Tail...>();
}
template <typename... Args> constexpr auto count_named_args() -> size_t {
return count<is_named_arg<Args>::value...>();
}
template <typename... Args>
constexpr auto count_statically_named_args() -> size_t {
return count<is_statically_named_arg<Args>::value...>();
}
struct unformattable {};
struct unformattable_char : unformattable {};
struct unformattable_const : unformattable {};
struct unformattable_pointer : unformattable {};
template <typename Char> struct string_value {
const Char* data;
size_t size;
};
template <typename Char> struct named_arg_value {
const named_arg_info<Char>* data;
size_t size;
};
template <typename Context> struct custom_value {
using parse_context = typename Context::parse_context_type;
void* value;
void (*format)(void* arg, parse_context& parse_ctx, Context& ctx);
};
// A formatting argument value.
template <typename Context> class value {
public:
using char_type = typename Context::char_type;
union {
monostate no_value;
int int_value;
unsigned uint_value;
long long long_long_value;
unsigned long long ulong_long_value;
int128_opt int128_value;
uint128_opt uint128_value;
bool bool_value;
char_type char_value;
float float_value;
double double_value;
long double long_double_value;
const void* pointer;
string_value<char_type> string;
custom_value<Context> custom;
named_arg_value<char_type> named_args;
};
constexpr FMT_INLINE value() : no_value() {}
constexpr FMT_INLINE value(int val) : int_value(val) {}
constexpr FMT_INLINE value(unsigned val) : uint_value(val) {}
constexpr FMT_INLINE value(long long val) : long_long_value(val) {}
constexpr FMT_INLINE value(unsigned long long val) : ulong_long_value(val) {}
FMT_INLINE value(int128_opt val) : int128_value(val) {}
FMT_INLINE value(uint128_opt val) : uint128_value(val) {}
constexpr FMT_INLINE value(float val) : float_value(val) {}
constexpr FMT_INLINE value(double val) : double_value(val) {}
FMT_INLINE value(long double val) : long_double_value(val) {}
constexpr FMT_INLINE value(bool val) : bool_value(val) {}
constexpr FMT_INLINE value(char_type val) : char_value(val) {}
FMT_CONSTEXPR FMT_INLINE value(const char_type* val) {
string.data = val;
if (is_constant_evaluated()) string.size = {};
}
FMT_CONSTEXPR FMT_INLINE value(basic_string_view<char_type> val) {
string.data = val.data();
string.size = val.size();
}
FMT_INLINE value(const void* val) : pointer(val) {}
FMT_INLINE value(const named_arg_info<char_type>* args, size_t size)
: named_args{args, size} {}
template <typename T> FMT_CONSTEXPR FMT_INLINE value(T& val) {
using value_type = remove_cvref_t<T>;
custom.value = const_cast<value_type*>(&val);
// Get the formatter type through the context to allow different contexts
// have different extension points, e.g. `formatter<T>` for `format` and
// `printf_formatter<T>` for `printf`.
custom.format = format_custom_arg<
value_type,
conditional_t<has_formatter<value_type, Context>::value,
typename Context::template formatter_type<value_type>,
fallback_formatter<value_type, char_type>>>;
}
value(unformattable);
value(unformattable_char);
value(unformattable_const);
value(unformattable_pointer);
private:
// Formats an argument of a custom type, such as a user-defined class.
template <typename T, typename Formatter>
static void format_custom_arg(void* arg,
typename Context::parse_context_type& parse_ctx,
Context& ctx) {
auto f = Formatter();
parse_ctx.advance_to(f.parse(parse_ctx));
using qualified_type =
conditional_t<has_const_formatter<T, Context>(), const T, T>;
ctx.advance_to(f.format(*static_cast<qualified_type*>(arg), ctx));
}
};
template <typename Context, typename T>
FMT_CONSTEXPR auto make_arg(T&& value) -> basic_format_arg<Context>;
// To minimize the number of types we need to deal with, long is translated
// either to int or to long long depending on its size.
enum { long_short = sizeof(long) == sizeof(int) };
using long_type = conditional_t<long_short, int, long long>;
using ulong_type = conditional_t<long_short, unsigned, unsigned long long>;
#ifdef __cpp_lib_byte
inline auto format_as(std::byte b) -> unsigned char {
return static_cast<unsigned char>(b);
}
#endif
template <typename T> struct has_format_as {
template <typename U, typename V = decltype(format_as(U())),
FMT_ENABLE_IF(std::is_enum<U>::value&& std::is_integral<V>::value)>
static auto check(U*) -> std::true_type;
static auto check(...) -> std::false_type;
enum { value = decltype(check(static_cast<T*>(nullptr)))::value };
};
// Maps formatting arguments to core types.
// arg_mapper reports errors by returning unformattable instead of using
// static_assert because it's used in the is_formattable trait.
template <typename Context> struct arg_mapper {
using char_type = typename Context::char_type;
FMT_CONSTEXPR FMT_INLINE auto map(signed char val) -> int { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(unsigned char val) -> unsigned {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(short val) -> int { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(unsigned short val) -> unsigned {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(int val) -> int { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(unsigned val) -> unsigned { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(long val) -> long_type { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(unsigned long val) -> ulong_type {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(long long val) -> long long { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(unsigned long long val)
-> unsigned long long {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(int128_opt val) -> int128_opt {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(uint128_opt val) -> uint128_opt {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(bool val) -> bool { return val; }
template <typename T, FMT_ENABLE_IF(std::is_same<T, char>::value ||
std::is_same<T, char_type>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(T val) -> char_type {
return val;
}
template <typename T, enable_if_t<(std::is_same<T, wchar_t>::value ||
#ifdef __cpp_char8_t
std::is_same<T, char8_t>::value ||
#endif
std::is_same<T, char16_t>::value ||
std::is_same<T, char32_t>::value) &&
!std::is_same<T, char_type>::value,
int> = 0>
FMT_CONSTEXPR FMT_INLINE auto map(T) -> unformattable_char {
return {};
}
FMT_CONSTEXPR FMT_INLINE auto map(float val) -> float { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(double val) -> double { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(long double val) -> long double {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(char_type* val) -> const char_type* {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(const char_type* val) -> const char_type* {
return val;
}
template <typename T,
FMT_ENABLE_IF(is_string<T>::value && !std::is_pointer<T>::value &&
std::is_same<char_type, char_t<T>>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(const T& val)
-> basic_string_view<char_type> {
return to_string_view(val);
}
template <typename T,
FMT_ENABLE_IF(is_string<T>::value && !std::is_pointer<T>::value &&
!std::is_same<char_type, char_t<T>>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(const T&) -> unformattable_char {
return {};
}
template <typename T,
FMT_ENABLE_IF(
std::is_convertible<T, basic_string_view<char_type>>::value &&
!is_string<T>::value && !has_formatter<T, Context>::value &&
!has_fallback_formatter<T, char_type>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(const T& val)
-> basic_string_view<char_type> {
return basic_string_view<char_type>(val);
}
template <typename T,
FMT_ENABLE_IF(
std::is_convertible<T, std_string_view<char_type>>::value &&
!std::is_convertible<T, basic_string_view<char_type>>::value &&
!is_string<T>::value && !has_formatter<T, Context>::value &&
!has_fallback_formatter<T, char_type>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(const T& val)
-> basic_string_view<char_type> {
return std_string_view<char_type>(val);
}
FMT_CONSTEXPR FMT_INLINE auto map(void* val) -> const void* { return val; }
FMT_CONSTEXPR FMT_INLINE auto map(const void* val) -> const void* {
return val;
}
FMT_CONSTEXPR FMT_INLINE auto map(std::nullptr_t val) -> const void* {
return val;
}
// We use SFINAE instead of a const T* parameter to avoid conflicting with
// the C array overload.
template <
typename T,
FMT_ENABLE_IF(
std::is_pointer<T>::value || std::is_member_pointer<T>::value ||
std::is_function<typename std::remove_pointer<T>::type>::value ||
(std::is_convertible<const T&, const void*>::value &&
!std::is_convertible<const T&, const char_type*>::value &&
!has_formatter<T, Context>::value))>
FMT_CONSTEXPR auto map(const T&) -> unformattable_pointer {
return {};
}
template <typename T, std::size_t N,
FMT_ENABLE_IF(!std::is_same<T, wchar_t>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(const T (&values)[N]) -> const T (&)[N] {
return values;
}
template <typename T,
FMT_ENABLE_IF(
std::is_enum<T>::value&& std::is_convertible<T, int>::value &&
!has_format_as<T>::value && !has_formatter<T, Context>::value &&
!has_fallback_formatter<T, char_type>::value)>
FMT_DEPRECATED FMT_CONSTEXPR FMT_INLINE auto map(const T& val)
-> decltype(std::declval<arg_mapper>().map(
static_cast<underlying_t<T>>(val))) {
return map(static_cast<underlying_t<T>>(val));
}
template <typename T, FMT_ENABLE_IF(has_format_as<T>::value &&
!has_formatter<T, Context>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(const T& val)
-> decltype(std::declval<arg_mapper>().map(format_as(T()))) {
return map(format_as(val));
}
template <typename T, typename U = remove_cvref_t<T>>
struct formattable
: bool_constant<has_const_formatter<U, Context>() ||
!std::is_const<remove_reference_t<T>>::value ||
has_fallback_formatter<U, char_type>::value> {};
#if (FMT_MSC_VERSION != 0 && FMT_MSC_VERSION < 1910) || \
FMT_ICC_VERSION != 0 || defined(__NVCC__)
// Workaround a bug in MSVC and Intel (Issue 2746).
template <typename T> FMT_CONSTEXPR FMT_INLINE auto do_map(T&& val) -> T& {
return val;
}
#else
template <typename T, FMT_ENABLE_IF(formattable<T>::value)>
FMT_CONSTEXPR FMT_INLINE auto do_map(T&& val) -> T& {
return val;
}
template <typename T, FMT_ENABLE_IF(!formattable<T>::value)>
FMT_CONSTEXPR FMT_INLINE auto do_map(T&&) -> unformattable_const {
return {};
}
#endif
template <typename T, typename U = remove_cvref_t<T>,
FMT_ENABLE_IF(!is_string<U>::value && !is_char<U>::value &&
!std::is_array<U>::value &&
!std::is_pointer<U>::value &&
!has_format_as<U>::value &&
(has_formatter<U, Context>::value ||
has_fallback_formatter<U, char_type>::value))>
FMT_CONSTEXPR FMT_INLINE auto map(T&& val)
-> decltype(this->do_map(std::forward<T>(val))) {
return do_map(std::forward<T>(val));
}
template <typename T, FMT_ENABLE_IF(is_named_arg<T>::value)>
FMT_CONSTEXPR FMT_INLINE auto map(const T& named_arg)
-> decltype(std::declval<arg_mapper>().map(named_arg.value)) {
return map(named_arg.value);
}
auto map(...) -> unformattable { return {}; }
};
// A type constant after applying arg_mapper<Context>.
template <typename T, typename Context>
using mapped_type_constant =
type_constant<decltype(arg_mapper<Context>().map(std::declval<const T&>())),
typename Context::char_type>;
enum { packed_arg_bits = 4 };
// Maximum number of arguments with packed types.
enum { max_packed_args = 62 / packed_arg_bits };
enum : unsigned long long { is_unpacked_bit = 1ULL << 63 };
enum : unsigned long long { has_named_args_bit = 1ULL << 62 };
FMT_END_DETAIL_NAMESPACE
// An output iterator that appends to a buffer.
// It is used to reduce symbol sizes for the common case.
class appender : public std::back_insert_iterator<detail::buffer<char>> {
using base = std::back_insert_iterator<detail::buffer<char>>;
template <typename T>
friend auto get_buffer(appender out) -> detail::buffer<char>& {
return detail::get_container(out);
}
public:
using std::back_insert_iterator<detail::buffer<char>>::back_insert_iterator;
appender(base it) noexcept : base(it) {}
FMT_UNCHECKED_ITERATOR(appender);
auto operator++() noexcept -> appender& { return *this; }
auto operator++(int) noexcept -> appender { return *this; }
};
// A formatting argument. It is a trivially copyable/constructible type to
// allow storage in basic_memory_buffer.
template <typename Context> class basic_format_arg {
private:
detail::value<Context> value_;
detail::type type_;
template <typename ContextType, typename T>
friend FMT_CONSTEXPR auto detail::make_arg(T&& value)
-> basic_format_arg<ContextType>;
template <typename Visitor, typename Ctx>
friend FMT_CONSTEXPR auto visit_format_arg(Visitor&& vis,
const basic_format_arg<Ctx>& arg)
-> decltype(vis(0));
friend class basic_format_args<Context>;
friend class dynamic_format_arg_store<Context>;
using char_type = typename Context::char_type;
template <typename T, typename Char, size_t NUM_ARGS, size_t NUM_NAMED_ARGS>
friend struct detail::arg_data;
basic_format_arg(const detail::named_arg_info<char_type>* args, size_t size)
: value_(args, size) {}
public:
class handle {
public:
explicit handle(detail::custom_value<Context> custom) : custom_(custom) {}
void format(typename Context::parse_context_type& parse_ctx,
Context& ctx) const {
custom_.format(custom_.value, parse_ctx, ctx);
}
private:
detail::custom_value<Context> custom_;
};
constexpr basic_format_arg() : type_(detail::type::none_type) {}
constexpr explicit operator bool() const noexcept {
return type_ != detail::type::none_type;
}
auto type() const -> detail::type { return type_; }
auto is_integral() const -> bool { return detail::is_integral_type(type_); }
auto is_arithmetic() const -> bool {
return detail::is_arithmetic_type(type_);
}
};
/**
\rst
Visits an argument dispatching to the appropriate visit method based on
the argument type. For example, if the argument type is ``double`` then
``vis(value)`` will be called with the value of type ``double``.
\endrst
*/
template <typename Visitor, typename Context>
FMT_CONSTEXPR FMT_INLINE auto visit_format_arg(
Visitor&& vis, const basic_format_arg<Context>& arg) -> decltype(vis(0)) {
switch (arg.type_) {
case detail::type::none_type:
break;
case detail::type::int_type:
return vis(arg.value_.int_value);
case detail::type::uint_type:
return vis(arg.value_.uint_value);
case detail::type::long_long_type:
return vis(arg.value_.long_long_value);
case detail::type::ulong_long_type:
return vis(arg.value_.ulong_long_value);
case detail::type::int128_type:
return vis(detail::convert_for_visit(arg.value_.int128_value));
case detail::type::uint128_type:
return vis(detail::convert_for_visit(arg.value_.uint128_value));
case detail::type::bool_type:
return vis(arg.value_.bool_value);
case detail::type::char_type:
return vis(arg.value_.char_value);
case detail::type::float_type:
return vis(arg.value_.float_value);
case detail::type::double_type:
return vis(arg.value_.double_value);
case detail::type::long_double_type:
return vis(arg.value_.long_double_value);
case detail::type::cstring_type:
return vis(arg.value_.string.data);
case detail::type::string_type:
using sv = basic_string_view<typename Context::char_type>;
return vis(sv(arg.value_.string.data, arg.value_.string.size));
case detail::type::pointer_type:
return vis(arg.value_.pointer);
case detail::type::custom_type:
return vis(typename basic_format_arg<Context>::handle(arg.value_.custom));
}
return vis(monostate());
}
FMT_BEGIN_DETAIL_NAMESPACE
template <typename Char, typename InputIt>
auto copy_str(InputIt begin, InputIt end, appender out) -> appender {
get_container(out).append(begin, end);
return out;
}
template <typename Char, typename R, typename OutputIt>
FMT_CONSTEXPR auto copy_str(R&& rng, OutputIt out) -> OutputIt {
return detail::copy_str<Char>(rng.begin(), rng.end(), out);
}
#if FMT_GCC_VERSION && FMT_GCC_VERSION < 500
// A workaround for gcc 4.8 to make void_t work in a SFINAE context.
template <typename... Ts> struct void_t_impl { using type = void; };
template <typename... Ts>
using void_t = typename detail::void_t_impl<Ts...>::type;
#else
template <typename...> using void_t = void;
#endif
template <typename It, typename T, typename Enable = void>
struct is_output_iterator : std::false_type {};
template <typename It, typename T>
struct is_output_iterator<
It, T,
void_t<typename std::iterator_traits<It>::iterator_category,
decltype(*std::declval<It>() = std::declval<T>())>>
: std::true_type {};
template <typename OutputIt>
struct is_back_insert_iterator : std::false_type {};
template <typename Container>
struct is_back_insert_iterator<std::back_insert_iterator<Container>>
: std::true_type {};
template <typename OutputIt>
struct is_contiguous_back_insert_iterator : std::false_type {};
template <typename Container>
struct is_contiguous_back_insert_iterator<std::back_insert_iterator<Container>>
: is_contiguous<Container> {};
template <>
struct is_contiguous_back_insert_iterator<appender> : std::true_type {};
// A type-erased reference to an std::locale to avoid a heavy <locale> include.
class locale_ref {
private:
const void* locale_; // A type-erased pointer to std::locale.
public:
constexpr locale_ref() : locale_(nullptr) {}
template <typename Locale> explicit locale_ref(const Locale& loc);
explicit operator bool() const noexcept { return locale_ != nullptr; }
template <typename Locale> auto get() const -> Locale;
};
template <typename> constexpr auto encode_types() -> unsigned long long {
return 0;
}
template <typename Context, typename Arg, typename... Args>
constexpr auto encode_types() -> unsigned long long {
return static_cast<unsigned>(mapped_type_constant<Arg, Context>::value) |
(encode_types<Context, Args...>() << packed_arg_bits);
}
template <typename Context, typename T>
FMT_CONSTEXPR FMT_INLINE auto make_value(T&& val) -> value<Context> {
const auto& arg = arg_mapper<Context>().map(FMT_FORWARD(val));
constexpr bool formattable_char =
!std::is_same<decltype(arg), const unformattable_char&>::value;
static_assert(formattable_char, "Mixing character types is disallowed.");
constexpr bool formattable_const =
!std::is_same<decltype(arg), const unformattable_const&>::value;
static_assert(formattable_const, "Cannot format a const argument.");
// Formatting of arbitrary pointers is disallowed. If you want to output
// a pointer cast it to "void *" or "const void *". In particular, this
// forbids formatting of "[const] volatile char *" which is printed as bool
// by iostreams.
constexpr bool formattable_pointer =
!std::is_same<decltype(arg), const unformattable_pointer&>::value;
static_assert(formattable_pointer,
"Formatting of non-void pointers is disallowed.");
constexpr bool formattable =
!std::is_same<decltype(arg), const unformattable&>::value;
static_assert(
formattable,
"Cannot format an argument. To make type T formattable provide a "
"formatter<T> specialization: https://fmt.dev/latest/api.html#udt");
return {arg};
}
template <typename Context, typename T>
FMT_CONSTEXPR auto make_arg(T&& value) -> basic_format_arg<Context> {
basic_format_arg<Context> arg;
arg.type_ = mapped_type_constant<T, Context>::value;
arg.value_ = make_value<Context>(value);
return arg;
}
// The type template parameter is there to avoid an ODR violation when using
// a fallback formatter in one translation unit and an implicit conversion in
// another (not recommended).
template <bool IS_PACKED, typename Context, type, typename T,
FMT_ENABLE_IF(IS_PACKED)>
FMT_CONSTEXPR FMT_INLINE auto make_arg(T&& val) -> value<Context> {
return make_value<Context>(val);
}
template <bool IS_PACKED, typename Context, type, typename T,
FMT_ENABLE_IF(!IS_PACKED)>
FMT_CONSTEXPR inline auto make_arg(T&& value) -> basic_format_arg<Context> {
return make_arg<Context>(value);
}
FMT_END_DETAIL_NAMESPACE
// Formatting context.
template <typename OutputIt, typename Char> class basic_format_context {
public:
/** The character type for the output. */
using char_type = Char;
private:
OutputIt out_;
basic_format_args<basic_format_context> args_;
detail::locale_ref loc_;
public:
using iterator = OutputIt;
using format_arg = basic_format_arg<basic_format_context>;
using parse_context_type = basic_format_parse_context<Char>;
template <typename T> using formatter_type = formatter<T, char_type>;
basic_format_context(basic_format_context&&) = default;
basic_format_context(const basic_format_context&) = delete;
void operator=(const basic_format_context&) = delete;
/**
Constructs a ``basic_format_context`` object. References to the arguments are
stored in the object so make sure they have appropriate lifetimes.
*/
constexpr basic_format_context(
OutputIt out, basic_format_args<basic_format_context> ctx_args,
detail::locale_ref loc = detail::locale_ref())
: out_(out), args_(ctx_args), loc_(loc) {}
constexpr auto arg(int id) const -> format_arg { return args_.get(id); }
FMT_CONSTEXPR auto arg(basic_string_view<char_type> name) -> format_arg {
return args_.get(name);
}
FMT_CONSTEXPR auto arg_id(basic_string_view<char_type> name) -> int {
return args_.get_id(name);
}
auto args() const -> const basic_format_args<basic_format_context>& {
return args_;
}
FMT_CONSTEXPR auto error_handler() -> detail::error_handler { return {}; }
void on_error(const char* message) { error_handler().on_error(message); }
// Returns an iterator to the beginning of the output range.
FMT_CONSTEXPR auto out() -> iterator { return out_; }
// Advances the begin iterator to ``it``.
void advance_to(iterator it) {
if (!detail::is_back_insert_iterator<iterator>()) out_ = it;
}
FMT_CONSTEXPR auto locale() -> detail::locale_ref { return loc_; }
};
template <typename Char>
using buffer_context =
basic_format_context<detail::buffer_appender<Char>, Char>;
using format_context = buffer_context<char>;
// Workaround an alias issue: https://stackoverflow.com/q/62767544/471164.
#define FMT_BUFFER_CONTEXT(Char) \
basic_format_context<detail::buffer_appender<Char>, Char>
template <typename T, typename Char = char>
using is_formattable = bool_constant<
!std::is_base_of<detail::unformattable,
decltype(detail::arg_mapper<buffer_context<Char>>().map(
std::declval<T>()))>::value &&
!detail::has_fallback_formatter<T, Char>::value>;
/**
\rst
An array of references to arguments. It can be implicitly converted into
`~fmt::basic_format_args` for passing into type-erased formatting functions
such as `~fmt::vformat`.
\endrst
*/
template <typename Context, typename... Args>
class format_arg_store
#if FMT_GCC_VERSION && FMT_GCC_VERSION < 409
// Workaround a GCC template argument substitution bug.
: public basic_format_args<Context>
#endif
{
private:
static const size_t num_args = sizeof...(Args);
static const size_t num_named_args = detail::count_named_args<Args...>();
static const bool is_packed = num_args <= detail::max_packed_args;
using value_type = conditional_t<is_packed, detail::value<Context>,
basic_format_arg<Context>>;
detail::arg_data<value_type, typename Context::char_type, num_args,
num_named_args>
data_;
friend class basic_format_args<Context>;
static constexpr unsigned long long desc =
(is_packed ? detail::encode_types<Context, Args...>()
: detail::is_unpacked_bit | num_args) |
(num_named_args != 0
? static_cast<unsigned long long>(detail::has_named_args_bit)
: 0);
public:
template <typename... T>
FMT_CONSTEXPR FMT_INLINE format_arg_store(T&&... args)
:
#if FMT_GCC_VERSION && FMT_GCC_VERSION < 409
basic_format_args<Context>(*this),
#endif
data_{detail::make_arg<
is_packed, Context,
detail::mapped_type_constant<remove_cvref_t<T>, Context>::value>(
FMT_FORWARD(args))...} {
detail::init_named_args(data_.named_args(), 0, 0, args...);
}
};
/**
\rst
Constructs a `~fmt::format_arg_store` object that contains references to
arguments and can be implicitly converted to `~fmt::format_args`. `Context`
can be omitted in which case it defaults to `~fmt::context`.
See `~fmt::arg` for lifetime considerations.
\endrst
*/
template <typename Context = format_context, typename... Args>
constexpr auto make_format_args(Args&&... args)
-> format_arg_store<Context, remove_cvref_t<Args>...> {
return {FMT_FORWARD(args)...};
}
/**
\rst
Returns a named argument to be used in a formatting function.
It should only be used in a call to a formatting function or
`dynamic_format_arg_store::push_back`.
**Example**::
fmt::print("Elapsed time: {s:.2f} seconds", fmt::arg("s", 1.23));
\endrst
*/
template <typename Char, typename T>
inline auto arg(const Char* name, const T& arg) -> detail::named_arg<Char, T> {
static_assert(!detail::is_named_arg<T>(), "nested named arguments");
return {name, arg};
}
/**
\rst
A view of a collection of formatting arguments. To avoid lifetime issues it
should only be used as a parameter type in type-erased functions such as
``vformat``::
void vlog(string_view format_str, format_args args); // OK
format_args args = make_format_args(42); // Error: dangling reference
\endrst
*/
template <typename Context> class basic_format_args {
public:
using size_type = int;
using format_arg = basic_format_arg<Context>;
private:
// A descriptor that contains information about formatting arguments.
// If the number of arguments is less or equal to max_packed_args then
// argument types are passed in the descriptor. This reduces binary code size
// per formatting function call.
unsigned long long desc_;
union {
// If is_packed() returns true then argument values are stored in values_;
// otherwise they are stored in args_. This is done to improve cache
// locality and reduce compiled code size since storing larger objects
// may require more code (at least on x86-64) even if the same amount of
// data is actually copied to stack. It saves ~10% on the bloat test.
const detail::value<Context>* values_;
const format_arg* args_;
};
constexpr auto is_packed() const -> bool {
return (desc_ & detail::is_unpacked_bit) == 0;
}
auto has_named_args() const -> bool {
return (desc_ & detail::has_named_args_bit) != 0;
}
FMT_CONSTEXPR auto type(int index) const -> detail::type {
int shift = index * detail::packed_arg_bits;
unsigned int mask = (1 << detail::packed_arg_bits) - 1;
return static_cast<detail::type>((desc_ >> shift) & mask);
}
constexpr FMT_INLINE basic_format_args(unsigned long long desc,
const detail::value<Context>* values)
: desc_(desc), values_(values) {}
constexpr basic_format_args(unsigned long long desc, const format_arg* args)
: desc_(desc), args_(args) {}
public:
constexpr basic_format_args() : desc_(0), args_(nullptr) {}
/**
\rst
Constructs a `basic_format_args` object from `~fmt::format_arg_store`.
\endrst
*/
template <typename... Args>
constexpr FMT_INLINE basic_format_args(
const format_arg_store<Context, Args...>& store)
: basic_format_args(format_arg_store<Context, Args...>::desc,
store.data_.args()) {}
/**
\rst
Constructs a `basic_format_args` object from
`~fmt::dynamic_format_arg_store`.
\endrst
*/
constexpr FMT_INLINE basic_format_args(
const dynamic_format_arg_store<Context>& store)
: basic_format_args(store.get_types(), store.data()) {}
/**
\rst
Constructs a `basic_format_args` object from a dynamic set of arguments.
\endrst
*/
constexpr basic_format_args(const format_arg* args, int count)
: basic_format_args(detail::is_unpacked_bit | detail::to_unsigned(count),
args) {}
/** Returns the argument with the specified id. */
FMT_CONSTEXPR auto get(int id) const -> format_arg {
format_arg arg;
if (!is_packed()) {
if (id < max_size()) arg = args_[id];
return arg;
}
if (id >= detail::max_packed_args) return arg;
arg.type_ = type(id);
if (arg.type_ == detail::type::none_type) return arg;
arg.value_ = values_[id];
return arg;
}
template <typename Char>
auto get(basic_string_view<Char> name) const -> format_arg {
int id = get_id(name);
return id >= 0 ? get(id) : format_arg();
}
template <typename Char>
auto get_id(basic_string_view<Char> name) const -> int {
if (!has_named_args()) return -1;
const auto& named_args =
(is_packed() ? values_[-1] : args_[-1].value_).named_args;
for (size_t i = 0; i < named_args.size; ++i) {
if (named_args.data[i].name == name) return named_args.data[i].id;
}
return -1;
}
auto max_size() const -> int {
unsigned long long max_packed = detail::max_packed_args;
return static_cast<int>(is_packed() ? max_packed
: desc_ & ~detail::is_unpacked_bit);
}
};
/** An alias to ``basic_format_args<format_context>``. */
// A separate type would result in shorter symbols but break ABI compatibility
// between clang and gcc on ARM (#1919).
using format_args = basic_format_args<format_context>;
// We cannot use enum classes as bit fields because of a gcc bug, so we put them
// in namespaces instead (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61414).
// Additionally, if an underlying type is specified, older gcc incorrectly warns
// that the type is too small. Both bugs are fixed in gcc 9.3.
#if FMT_GCC_VERSION && FMT_GCC_VERSION < 903
# define FMT_ENUM_UNDERLYING_TYPE(type)
#else
# define FMT_ENUM_UNDERLYING_TYPE(type) : type
#endif
namespace align {
enum type FMT_ENUM_UNDERLYING_TYPE(unsigned char){none, left, right, center,
numeric};
}
using align_t = align::type;
namespace sign {
enum type FMT_ENUM_UNDERLYING_TYPE(unsigned char){none, minus, plus, space};
}
using sign_t = sign::type;
FMT_BEGIN_DETAIL_NAMESPACE
// Workaround an array initialization issue in gcc 4.8.
template <typename Char> struct fill_t {
private:
enum { max_size = 4 };
Char data_[max_size] = {Char(' '), Char(0), Char(0), Char(0)};
unsigned char size_ = 1;
public:
FMT_CONSTEXPR void operator=(basic_string_view<Char> s) {
auto size = s.size();
if (size > max_size) return throw_format_error("invalid fill");
for (size_t i = 0; i < size; ++i) data_[i] = s[i];
size_ = static_cast<unsigned char>(size);
}
constexpr auto size() const -> size_t { return size_; }
constexpr auto data() const -> const Char* { return data_; }
FMT_CONSTEXPR auto operator[](size_t index) -> Char& { return data_[index]; }
FMT_CONSTEXPR auto operator[](size_t index) const -> const Char& {
return data_[index];
}
};
FMT_END_DETAIL_NAMESPACE
enum class presentation_type : unsigned char {
none,
// Integer types should go first,
dec, // 'd'
oct, // 'o'
hex_lower, // 'x'
hex_upper, // 'X'
bin_lower, // 'b'
bin_upper, // 'B'
hexfloat_lower, // 'a'
hexfloat_upper, // 'A'
exp_lower, // 'e'
exp_upper, // 'E'
fixed_lower, // 'f'
fixed_upper, // 'F'
general_lower, // 'g'
general_upper, // 'G'
chr, // 'c'
string, // 's'
pointer, // 'p'
debug // '?'
};
// Format specifiers for built-in and string types.
template <typename Char> struct basic_format_specs {
int width;
int precision;
presentation_type type;
align_t align : 4;
sign_t sign : 3;
bool alt : 1; // Alternate form ('#').
bool localized : 1;
detail::fill_t<Char> fill;
constexpr basic_format_specs()
: width(0),
precision(-1),
type(presentation_type::none),
align(align::none),
sign(sign::none),
alt(false),
localized(false) {}
};
using format_specs = basic_format_specs<char>;
FMT_BEGIN_DETAIL_NAMESPACE
enum class arg_id_kind { none, index, name };
// An argument reference.
template <typename Char> struct arg_ref {
FMT_CONSTEXPR arg_ref() : kind(arg_id_kind::none), val() {}
FMT_CONSTEXPR explicit arg_ref(int index)
: kind(arg_id_kind::index), val(index) {}
FMT_CONSTEXPR explicit arg_ref(basic_string_view<Char> name)
: kind(arg_id_kind::name), val(name) {}
FMT_CONSTEXPR auto operator=(int idx) -> arg_ref& {
kind = arg_id_kind::index;
val.index = idx;
return *this;
}
arg_id_kind kind;
union value {
FMT_CONSTEXPR value(int id = 0) : index{id} {}
FMT_CONSTEXPR value(basic_string_view<Char> n) : name(n) {}
int index;
basic_string_view<Char> name;
} val;
};
// Format specifiers with width and precision resolved at formatting rather
// than parsing time to allow re-using the same parsed specifiers with
// different sets of arguments (precompilation of format strings).
template <typename Char>
struct dynamic_format_specs : basic_format_specs<Char> {
arg_ref<Char> width_ref;
arg_ref<Char> precision_ref;
};
struct auto_id {};
// A format specifier handler that sets fields in basic_format_specs.
template <typename Char> class specs_setter {
protected:
basic_format_specs<Char>& specs_;
public:
explicit FMT_CONSTEXPR specs_setter(basic_format_specs<Char>& specs)
: specs_(specs) {}
FMT_CONSTEXPR specs_setter(const specs_setter& other)
: specs_(other.specs_) {}
FMT_CONSTEXPR void on_align(align_t align) { specs_.align = align; }
FMT_CONSTEXPR void on_fill(basic_string_view<Char> fill) {
specs_.fill = fill;
}
FMT_CONSTEXPR void on_sign(sign_t s) { specs_.sign = s; }
FMT_CONSTEXPR void on_hash() { specs_.alt = true; }
FMT_CONSTEXPR void on_localized() { specs_.localized = true; }
FMT_CONSTEXPR void on_zero() {
if (specs_.align == align::none) specs_.align = align::numeric;
specs_.fill[0] = Char('0');
}
FMT_CONSTEXPR void on_width(int width) { specs_.width = width; }
FMT_CONSTEXPR void on_precision(int precision) {
specs_.precision = precision;
}
FMT_CONSTEXPR void end_precision() {}
FMT_CONSTEXPR void on_type(presentation_type type) { specs_.type = type; }
};
// Format spec handler that saves references to arguments representing dynamic
// width and precision to be resolved at formatting time.
template <typename ParseContext>
class dynamic_specs_handler
: public specs_setter<typename ParseContext::char_type> {
public:
using char_type = typename ParseContext::char_type;
FMT_CONSTEXPR dynamic_specs_handler(dynamic_format_specs<char_type>& specs,
ParseContext& ctx)
: specs_setter<char_type>(specs), specs_(specs), context_(ctx) {}
FMT_CONSTEXPR dynamic_specs_handler(const dynamic_specs_handler& other)
: specs_setter<char_type>(other),
specs_(other.specs_),
context_(other.context_) {}
template <typename Id> FMT_CONSTEXPR void on_dynamic_width(Id arg_id) {
specs_.width_ref = make_arg_ref(arg_id);
}
template <typename Id> FMT_CONSTEXPR void on_dynamic_precision(Id arg_id) {
specs_.precision_ref = make_arg_ref(arg_id);
}
FMT_CONSTEXPR void on_error(const char* message) {
context_.on_error(message);
}
private:
dynamic_format_specs<char_type>& specs_;
ParseContext& context_;
using arg_ref_type = arg_ref<char_type>;
FMT_CONSTEXPR auto make_arg_ref(int arg_id) -> arg_ref_type {
context_.check_arg_id(arg_id);
context_.check_dynamic_spec(arg_id);
return arg_ref_type(arg_id);
}
FMT_CONSTEXPR auto make_arg_ref(auto_id) -> arg_ref_type {
int arg_id = context_.next_arg_id();
context_.check_dynamic_spec(arg_id);
return arg_ref_type(arg_id);
}
FMT_CONSTEXPR auto make_arg_ref(basic_string_view<char_type> arg_id)
-> arg_ref_type {
context_.check_arg_id(arg_id);
basic_string_view<char_type> format_str(
context_.begin(), to_unsigned(context_.end() - context_.begin()));
return arg_ref_type(arg_id);
}
};
template <typename Char> constexpr bool is_ascii_letter(Char c) {
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
}
// Converts a character to ASCII. Returns a number > 127 on conversion failure.
template <typename Char, FMT_ENABLE_IF(std::is_integral<Char>::value)>
constexpr auto to_ascii(Char c) -> Char {
return c;
}
template <typename Char, FMT_ENABLE_IF(std::is_enum<Char>::value)>
constexpr auto to_ascii(Char c) -> underlying_t<Char> {
return c;
}
FMT_CONSTEXPR inline auto code_point_length_impl(char c) -> int {
return "\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\0\0\0\0\0\0\0\0\2\2\2\2\3\3\4"
[static_cast<unsigned char>(c) >> 3];
}
template <typename Char>
FMT_CONSTEXPR auto code_point_length(const Char* begin) -> int {
if (const_check(sizeof(Char) != 1)) return 1;
int len = code_point_length_impl(static_cast<char>(*begin));
// Compute the pointer to the next character early so that the next
// iteration can start working on the next character. Neither Clang
// nor GCC figure out this reordering on their own.
return len + !len;
}
// Return the result via the out param to workaround gcc bug 77539.
template <bool IS_CONSTEXPR, typename T, typename Ptr = const T*>
FMT_CONSTEXPR auto find(Ptr first, Ptr last, T value, Ptr& out) -> bool {
for (out = first; out != last; ++out) {
if (*out == value) return true;
}
return false;
}
template <>
inline auto find<false, char>(const char* first, const char* last, char value,
const char*& out) -> bool {
out = static_cast<const char*>(
std::memchr(first, value, to_unsigned(last - first)));
return out != nullptr;
}
// Parses the range [begin, end) as an unsigned integer. This function assumes
// that the range is non-empty and the first character is a digit.
template <typename Char>
FMT_CONSTEXPR auto parse_nonnegative_int(const Char*& begin, const Char* end,
int error_value) noexcept -> int {
FMT_ASSERT(begin != end && '0' <= *begin && *begin <= '9', "");
unsigned value = 0, prev = 0;
auto p = begin;
do {
prev = value;
value = value * 10 + unsigned(*p - '0');
++p;
} while (p != end && '0' <= *p && *p <= '9');
auto num_digits = p - begin;
begin = p;
if (num_digits <= std::numeric_limits<int>::digits10)
return static_cast<int>(value);
// Check for overflow.
const unsigned max = to_unsigned((std::numeric_limits<int>::max)());
return num_digits == std::numeric_limits<int>::digits10 + 1 &&
prev * 10ull + unsigned(p[-1] - '0') <= max
? static_cast<int>(value)
: error_value;
}
// Parses fill and alignment.
template <typename Char, typename Handler>
FMT_CONSTEXPR auto parse_align(const Char* begin, const Char* end,
Handler&& handler) -> const Char* {
FMT_ASSERT(begin != end, "");
auto align = align::none;
auto p = begin + code_point_length(begin);
if (end - p <= 0) p = begin;
for (;;) {
switch (to_ascii(*p)) {
case '<':
align = align::left;
break;
case '>':
align = align::right;
break;
case '^':
align = align::center;
break;
default:
break;
}
if (align != align::none) {
if (p != begin) {
auto c = *begin;
if (c == '{')
return handler.on_error("invalid fill character '{'"), begin;
handler.on_fill(basic_string_view<Char>(begin, to_unsigned(p - begin)));
begin = p + 1;
} else
++begin;
handler.on_align(align);
break;
} else if (p == begin) {
break;
}
p = begin;
}
return begin;
}
template <typename Char> FMT_CONSTEXPR bool is_name_start(Char c) {
return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || '_' == c;
}
template <typename Char, typename IDHandler>
FMT_CONSTEXPR auto do_parse_arg_id(const Char* begin, const Char* end,
IDHandler&& handler) -> const Char* {
FMT_ASSERT(begin != end, "");
Char c = *begin;
if (c >= '0' && c <= '9') {
int index = 0;
if (c != '0')
index =
parse_nonnegative_int(begin, end, (std::numeric_limits<int>::max)());
else
++begin;
if (begin == end || (*begin != '}' && *begin != ':'))
handler.on_error("invalid format string");
else
handler(index);
return begin;
}
if (!is_name_start(c)) {
handler.on_error("invalid format string");
return begin;
}
auto it = begin;
do {
++it;
} while (it != end && (is_name_start(c = *it) || ('0' <= c && c <= '9')));
handler(basic_string_view<Char>(begin, to_unsigned(it - begin)));
return it;
}
template <typename Char, typename IDHandler>
FMT_CONSTEXPR FMT_INLINE auto parse_arg_id(const Char* begin, const Char* end,
IDHandler&& handler) -> const Char* {
Char c = *begin;
if (c != '}' && c != ':') return do_parse_arg_id(begin, end, handler);
handler();
return begin;
}
template <typename Char, typename Handler>
FMT_CONSTEXPR auto parse_width(const Char* begin, const Char* end,
Handler&& handler) -> const Char* {
using detail::auto_id;
struct width_adapter {
Handler& handler;
FMT_CONSTEXPR void operator()() { handler.on_dynamic_width(auto_id()); }
FMT_CONSTEXPR void operator()(int id) { handler.on_dynamic_width(id); }
FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
handler.on_dynamic_width(id);
}
FMT_CONSTEXPR void on_error(const char* message) {
if (message) handler.on_error(message);
}
};
FMT_ASSERT(begin != end, "");
if ('0' <= *begin && *begin <= '9') {
int width = parse_nonnegative_int(begin, end, -1);
if (width != -1)
handler.on_width(width);
else
handler.on_error("number is too big");
} else if (*begin == '{') {
++begin;
if (begin != end) begin = parse_arg_id(begin, end, width_adapter{handler});
if (begin == end || *begin != '}')
return handler.on_error("invalid format string"), begin;
++begin;
}
return begin;
}
template <typename Char, typename Handler>
FMT_CONSTEXPR auto parse_precision(const Char* begin, const Char* end,
Handler&& handler) -> const Char* {
using detail::auto_id;
struct precision_adapter {
Handler& handler;
FMT_CONSTEXPR void operator()() { handler.on_dynamic_precision(auto_id()); }
FMT_CONSTEXPR void operator()(int id) { handler.on_dynamic_precision(id); }
FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
handler.on_dynamic_precision(id);
}
FMT_CONSTEXPR void on_error(const char* message) {
if (message) handler.on_error(message);
}
};
++begin;
auto c = begin != end ? *begin : Char();
if ('0' <= c && c <= '9') {
auto precision = parse_nonnegative_int(begin, end, -1);
if (precision != -1)
handler.on_precision(precision);
else
handler.on_error("number is too big");
} else if (c == '{') {
++begin;
if (begin != end)
begin = parse_arg_id(begin, end, precision_adapter{handler});
if (begin == end || *begin++ != '}')
return handler.on_error("invalid format string"), begin;
} else {
return handler.on_error("missing precision specifier"), begin;
}
handler.end_precision();
return begin;
}
template <typename Char>
FMT_CONSTEXPR auto parse_presentation_type(Char type) -> presentation_type {
switch (to_ascii(type)) {
case 'd':
return presentation_type::dec;
case 'o':
return presentation_type::oct;
case 'x':
return presentation_type::hex_lower;
case 'X':
return presentation_type::hex_upper;
case 'b':
return presentation_type::bin_lower;
case 'B':
return presentation_type::bin_upper;
case 'a':
return presentation_type::hexfloat_lower;
case 'A':
return presentation_type::hexfloat_upper;
case 'e':
return presentation_type::exp_lower;
case 'E':
return presentation_type::exp_upper;
case 'f':
return presentation_type::fixed_lower;
case 'F':
return presentation_type::fixed_upper;
case 'g':
return presentation_type::general_lower;
case 'G':
return presentation_type::general_upper;
case 'c':
return presentation_type::chr;
case 's':
return presentation_type::string;
case 'p':
return presentation_type::pointer;
case '?':
return presentation_type::debug;
default:
return presentation_type::none;
}
}
// Parses standard format specifiers and sends notifications about parsed
// components to handler.
template <typename Char, typename SpecHandler>
FMT_CONSTEXPR FMT_INLINE auto parse_format_specs(const Char* begin,
const Char* end,
SpecHandler&& handler)
-> const Char* {
if (1 < end - begin && begin[1] == '}' && is_ascii_letter(*begin) &&
*begin != 'L') {
presentation_type type = parse_presentation_type(*begin++);
if (type == presentation_type::none)
handler.on_error("invalid type specifier");
handler.on_type(type);
return begin;
}
if (begin == end) return begin;
begin = parse_align(begin, end, handler);
if (begin == end) return begin;
// Parse sign.
switch (to_ascii(*begin)) {
case '+':
handler.on_sign(sign::plus);
++begin;
break;
case '-':
handler.on_sign(sign::minus);
++begin;
break;
case ' ':
handler.on_sign(sign::space);
++begin;
break;
default:
break;
}
if (begin == end) return begin;
if (*begin == '#') {
handler.on_hash();
if (++begin == end) return begin;
}
// Parse zero flag.
if (*begin == '0') {
handler.on_zero();
if (++begin == end) return begin;
}
begin = parse_width(begin, end, handler);
if (begin == end) return begin;
// Parse precision.
if (*begin == '.') {
begin = parse_precision(begin, end, handler);
if (begin == end) return begin;
}
if (*begin == 'L') {
handler.on_localized();
++begin;
}
// Parse type.
if (begin != end && *begin != '}') {
presentation_type type = parse_presentation_type(*begin++);
if (type == presentation_type::none)
handler.on_error("invalid type specifier");
handler.on_type(type);
}
return begin;
}
template <typename Char, typename Handler>
FMT_CONSTEXPR auto parse_replacement_field(const Char* begin, const Char* end,
Handler&& handler) -> const Char* {
struct id_adapter {
Handler& handler;
int arg_id;
FMT_CONSTEXPR void operator()() { arg_id = handler.on_arg_id(); }
FMT_CONSTEXPR void operator()(int id) { arg_id = handler.on_arg_id(id); }
FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
arg_id = handler.on_arg_id(id);
}
FMT_CONSTEXPR void on_error(const char* message) {
if (message) handler.on_error(message);
}
};
++begin;
if (begin == end) return handler.on_error("invalid format string"), end;
if (*begin == '}') {
handler.on_replacement_field(handler.on_arg_id(), begin);
} else if (*begin == '{') {
handler.on_text(begin, begin + 1);
} else {
auto adapter = id_adapter{handler, 0};
begin = parse_arg_id(begin, end, adapter);
Char c = begin != end ? *begin : Char();
if (c == '}') {
handler.on_replacement_field(adapter.arg_id, begin);
} else if (c == ':') {
begin = handler.on_format_specs(adapter.arg_id, begin + 1, end);
if (begin == end || *begin != '}')
return handler.on_error("unknown format specifier"), end;
} else {
return handler.on_error("missing '}' in format string"), end;
}
}
return begin + 1;
}
template <bool IS_CONSTEXPR, typename Char, typename Handler>
FMT_CONSTEXPR FMT_INLINE void parse_format_string(
basic_string_view<Char> format_str, Handler&& handler) {
// Workaround a name-lookup bug in MSVC's modules implementation.
using detail::find;
auto begin = format_str.data();
auto end = begin + format_str.size();
if (end - begin < 32) {
// Use a simple loop instead of memchr for small strings.
const Char* p = begin;
while (p != end) {
auto c = *p++;
if (c == '{') {
handler.on_text(begin, p - 1);
begin = p = parse_replacement_field(p - 1, end, handler);
} else if (c == '}') {
if (p == end || *p != '}')
return handler.on_error("unmatched '}' in format string");
handler.on_text(begin, p);
begin = ++p;
}
}
handler.on_text(begin, end);
return;
}
struct writer {
FMT_CONSTEXPR void operator()(const Char* from, const Char* to) {
if (from == to) return;
for (;;) {
const Char* p = nullptr;
if (!find<IS_CONSTEXPR>(from, to, Char('}'), p))
return handler_.on_text(from, to);
++p;
if (p == to || *p != '}')
return handler_.on_error("unmatched '}' in format string");
handler_.on_text(from, p);
from = p + 1;
}
}
Handler& handler_;
} write = {handler};
while (begin != end) {
// Doing two passes with memchr (one for '{' and another for '}') is up to
// 2.5x faster than the naive one-pass implementation on big format strings.
const Char* p = begin;
if (*begin != '{' && !find<IS_CONSTEXPR>(begin + 1, end, Char('{'), p))
return write(begin, end);
write(begin, p);
begin = parse_replacement_field(p, end, handler);
}
}
template <typename T, bool = is_named_arg<T>::value> struct strip_named_arg {
using type = T;
};
template <typename T> struct strip_named_arg<T, true> {
using type = remove_cvref_t<decltype(T::value)>;
};
template <typename T, typename ParseContext>
FMT_CONSTEXPR auto parse_format_specs(ParseContext& ctx)
-> decltype(ctx.begin()) {
using char_type = typename ParseContext::char_type;
using context = buffer_context<char_type>;
using stripped_type = typename strip_named_arg<T>::type;
using mapped_type = conditional_t<
mapped_type_constant<T, context>::value != type::custom_type,
decltype(arg_mapper<context>().map(std::declval<const T&>())),
stripped_type>;
auto f = conditional_t<has_formatter<mapped_type, context>::value,
formatter<mapped_type, char_type>,
fallback_formatter<stripped_type, char_type>>();
return f.parse(ctx);
}
template <typename ErrorHandler>
FMT_CONSTEXPR void check_int_type_spec(presentation_type type,
ErrorHandler&& eh) {
if (type > presentation_type::bin_upper && type != presentation_type::chr)
eh.on_error("invalid type specifier");
}
// Checks char specs and returns true if the type spec is char (and not int).
template <typename Char, typename ErrorHandler = error_handler>
FMT_CONSTEXPR auto check_char_specs(const basic_format_specs<Char>& specs,
ErrorHandler&& eh = {}) -> bool {
if (specs.type != presentation_type::none &&
specs.type != presentation_type::chr &&
specs.type != presentation_type::debug) {
check_int_type_spec(specs.type, eh);
return false;
}
if (specs.align == align::numeric || specs.sign != sign::none || specs.alt)
eh.on_error("invalid format specifier for char");
return true;
}
// A floating-point presentation format.
enum class float_format : unsigned char {
general, // General: exponent notation or fixed point based on magnitude.
exp, // Exponent notation with the default precision of 6, e.g. 1.2e-3.
fixed, // Fixed point with the default precision of 6, e.g. 0.0012.
hex
};
struct float_specs {
int precision;
float_format format : 8;
sign_t sign : 8;
bool upper : 1;
bool locale : 1;
bool binary32 : 1;
bool showpoint : 1;
};
template <typename ErrorHandler = error_handler, typename Char>
FMT_CONSTEXPR auto parse_float_type_spec(const basic_format_specs<Char>& specs,
ErrorHandler&& eh = {})
-> float_specs {
auto result = float_specs();
result.showpoint = specs.alt;
result.locale = specs.localized;
switch (specs.type) {
case presentation_type::none:
result.format = float_format::general;
break;
case presentation_type::general_upper:
result.upper = true;
FMT_FALLTHROUGH;
case presentation_type::general_lower:
result.format = float_format::general;
break;
case presentation_type::exp_upper:
result.upper = true;
FMT_FALLTHROUGH;
case presentation_type::exp_lower:
result.format = float_format::exp;
result.showpoint |= specs.precision != 0;
break;
case presentation_type::fixed_upper:
result.upper = true;
FMT_FALLTHROUGH;
case presentation_type::fixed_lower:
result.format = float_format::fixed;
result.showpoint |= specs.precision != 0;
break;
case presentation_type::hexfloat_upper:
result.upper = true;
FMT_FALLTHROUGH;
case presentation_type::hexfloat_lower:
result.format = float_format::hex;
break;
default:
eh.on_error("invalid type specifier");
break;
}
return result;
}
template <typename ErrorHandler = error_handler>
FMT_CONSTEXPR auto check_cstring_type_spec(presentation_type type,
ErrorHandler&& eh = {}) -> bool {
if (type == presentation_type::none || type == presentation_type::string ||
type == presentation_type::debug)
return true;
if (type != presentation_type::pointer) eh.on_error("invalid type specifier");
return false;
}
template <typename ErrorHandler = error_handler>
FMT_CONSTEXPR void check_string_type_spec(presentation_type type,
ErrorHandler&& eh = {}) {
if (type != presentation_type::none && type != presentation_type::string &&
type != presentation_type::debug)
eh.on_error("invalid type specifier");
}
template <typename ErrorHandler>
FMT_CONSTEXPR void check_pointer_type_spec(presentation_type type,
ErrorHandler&& eh) {
if (type != presentation_type::none && type != presentation_type::pointer)
eh.on_error("invalid type specifier");
}
// A parse_format_specs handler that checks if specifiers are consistent with
// the argument type.
template <typename Handler> class specs_checker : public Handler {
private:
detail::type arg_type_;
FMT_CONSTEXPR void require_numeric_argument() {
if (!is_arithmetic_type(arg_type_))
this->on_error("format specifier requires numeric argument");
}
public:
FMT_CONSTEXPR specs_checker(const Handler& handler, detail::type arg_type)
: Handler(handler), arg_type_(arg_type) {}
FMT_CONSTEXPR void on_align(align_t align) {
if (align == align::numeric) require_numeric_argument();
Handler::on_align(align);
}
FMT_CONSTEXPR void on_sign(sign_t s) {
require_numeric_argument();
if (is_integral_type(arg_type_) && arg_type_ != type::int_type &&
arg_type_ != type::long_long_type && arg_type_ != type::int128_type &&
arg_type_ != type::char_type) {
this->on_error("format specifier requires signed argument");
}
Handler::on_sign(s);
}
FMT_CONSTEXPR void on_hash() {
require_numeric_argument();
Handler::on_hash();
}
FMT_CONSTEXPR void on_localized() {
require_numeric_argument();
Handler::on_localized();
}
FMT_CONSTEXPR void on_zero() {
require_numeric_argument();
Handler::on_zero();
}
FMT_CONSTEXPR void end_precision() {
if (is_integral_type(arg_type_) || arg_type_ == type::pointer_type)
this->on_error("precision not allowed for this argument type");
}
};
constexpr int invalid_arg_index = -1;
#if FMT_USE_NONTYPE_TEMPLATE_ARGS
template <int N, typename T, typename... Args, typename Char>
constexpr auto get_arg_index_by_name(basic_string_view<Char> name) -> int {
if constexpr (detail::is_statically_named_arg<T>()) {
if (name == T::name) return N;
}
if constexpr (sizeof...(Args) > 0)
return get_arg_index_by_name<N + 1, Args...>(name);
(void)name; // Workaround an MSVC bug about "unused" parameter.
return invalid_arg_index;
}
#endif
template <typename... Args, typename Char>
FMT_CONSTEXPR auto get_arg_index_by_name(basic_string_view<Char> name) -> int {
#if FMT_USE_NONTYPE_TEMPLATE_ARGS
if constexpr (sizeof...(Args) > 0)
return get_arg_index_by_name<0, Args...>(name);
#endif
(void)name;
return invalid_arg_index;
}
template <typename Char, typename ErrorHandler, typename... Args>
class format_string_checker {
private:
// In the future basic_format_parse_context will replace compile_parse_context
// here and will use is_constant_evaluated and downcasting to access the data
// needed for compile-time checks: https://godbolt.org/z/GvWzcTjh1.
using parse_context_type = compile_parse_context<Char, ErrorHandler>;
static constexpr int num_args = sizeof...(Args);
// Format specifier parsing function.
using parse_func = const Char* (*)(parse_context_type&);
parse_context_type context_;
parse_func parse_funcs_[num_args > 0 ? static_cast<size_t>(num_args) : 1];
type types_[num_args > 0 ? static_cast<size_t>(num_args) : 1];
public:
explicit FMT_CONSTEXPR format_string_checker(
basic_string_view<Char> format_str, ErrorHandler eh)
: context_(format_str, num_args, types_, eh),
parse_funcs_{&parse_format_specs<Args, parse_context_type>...},
types_{
mapped_type_constant<Args,
basic_format_context<Char*, Char>>::value...} {
}
FMT_CONSTEXPR void on_text(const Char*, const Char*) {}
FMT_CONSTEXPR auto on_arg_id() -> int { return context_.next_arg_id(); }
FMT_CONSTEXPR auto on_arg_id(int id) -> int {
return context_.check_arg_id(id), id;
}
FMT_CONSTEXPR auto on_arg_id(basic_string_view<Char> id) -> int {
#if FMT_USE_NONTYPE_TEMPLATE_ARGS
auto index = get_arg_index_by_name<Args...>(id);
if (index == invalid_arg_index) on_error("named argument is not found");
return context_.check_arg_id(index), index;
#else
(void)id;
on_error("compile-time checks for named arguments require C++20 support");
return 0;
#endif
}
FMT_CONSTEXPR void on_replacement_field(int, const Char*) {}
FMT_CONSTEXPR auto on_format_specs(int id, const Char* begin, const Char*)
-> const Char* {
context_.advance_to(context_.begin() + (begin - &*context_.begin()));
// id >= 0 check is a workaround for gcc 10 bug (#2065).
return id >= 0 && id < num_args ? parse_funcs_[id](context_) : begin;
}
FMT_CONSTEXPR void on_error(const char* message) {
context_.on_error(message);
}
};
// Reports a compile-time error if S is not a valid format string.
template <typename..., typename S, FMT_ENABLE_IF(!is_compile_string<S>::value)>
FMT_INLINE void check_format_string(const S&) {
#ifdef FMT_ENFORCE_COMPILE_STRING
static_assert(is_compile_string<S>::value,
"FMT_ENFORCE_COMPILE_STRING requires all format strings to use "
"FMT_STRING.");
#endif
}
template <typename... Args, typename S,
FMT_ENABLE_IF(is_compile_string<S>::value)>
void check_format_string(S format_str) {
FMT_CONSTEXPR auto s = basic_string_view<typename S::char_type>(format_str);
using checker = format_string_checker<typename S::char_type, error_handler,
remove_cvref_t<Args>...>;
FMT_CONSTEXPR bool invalid_format =
(parse_format_string<true>(s, checker(s, {})), true);
ignore_unused(invalid_format);
}
template <typename Char>
void vformat_to(
buffer<Char>& buf, basic_string_view<Char> fmt,
basic_format_args<FMT_BUFFER_CONTEXT(type_identity_t<Char>)> args,
locale_ref loc = {});
FMT_API void vprint_mojibake(std::FILE*, string_view, format_args);
#ifndef _WIN32
inline void vprint_mojibake(std::FILE*, string_view, format_args) {}
#endif
FMT_END_DETAIL_NAMESPACE
// A formatter specialization for the core types corresponding to detail::type
// constants.
template <typename T, typename Char>
struct formatter<T, Char,
enable_if_t<detail::type_constant<T, Char>::value !=
detail::type::custom_type>> {
private:
detail::dynamic_format_specs<Char> specs_;
public:
// Parses format specifiers stopping either at the end of the range or at the
// terminating '}'.
template <typename ParseContext>
FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
auto begin = ctx.begin(), end = ctx.end();
if (begin == end) return begin;
using handler_type = detail::dynamic_specs_handler<ParseContext>;
auto type = detail::type_constant<T, Char>::value;
auto checker =
detail::specs_checker<handler_type>(handler_type(specs_, ctx), type);
auto it = detail::parse_format_specs(begin, end, checker);
auto eh = ctx.error_handler();
switch (type) {
case detail::type::none_type:
FMT_ASSERT(false, "invalid argument type");
break;
case detail::type::bool_type:
if (specs_.type == presentation_type::none ||
specs_.type == presentation_type::string) {
break;
}
FMT_FALLTHROUGH;
case detail::type::int_type:
case detail::type::uint_type:
case detail::type::long_long_type:
case detail::type::ulong_long_type:
case detail::type::int128_type:
case detail::type::uint128_type:
detail::check_int_type_spec(specs_.type, eh);
break;
case detail::type::char_type:
detail::check_char_specs(specs_, eh);
break;
case detail::type::float_type:
if (detail::const_check(FMT_USE_FLOAT))
detail::parse_float_type_spec(specs_, eh);
else
FMT_ASSERT(false, "float support disabled");
break;
case detail::type::double_type:
if (detail::const_check(FMT_USE_DOUBLE))
detail::parse_float_type_spec(specs_, eh);
else
FMT_ASSERT(false, "double support disabled");
break;
case detail::type::long_double_type:
if (detail::const_check(FMT_USE_LONG_DOUBLE))
detail::parse_float_type_spec(specs_, eh);
else
FMT_ASSERT(false, "long double support disabled");
break;
case detail::type::cstring_type:
detail::check_cstring_type_spec(specs_.type, eh);
break;
case detail::type::string_type:
detail::check_string_type_spec(specs_.type, eh);
break;
case detail::type::pointer_type:
detail::check_pointer_type_spec(specs_.type, eh);
break;
case detail::type::custom_type:
// Custom format specifiers are checked in parse functions of
// formatter specializations.
break;
}
return it;
}
template <detail::type U = detail::type_constant<T, Char>::value,
enable_if_t<(U == detail::type::string_type ||
U == detail::type::cstring_type ||
U == detail::type::char_type),
int> = 0>
FMT_CONSTEXPR void set_debug_format() {
specs_.type = presentation_type::debug;
}
template <typename FormatContext>
FMT_CONSTEXPR auto format(const T& val, FormatContext& ctx) const
-> decltype(ctx.out());
};
#define FMT_FORMAT_AS(Type, Base) \
template <typename Char> \
struct formatter<Type, Char> : formatter<Base, Char> { \
template <typename FormatContext> \
auto format(Type const& val, FormatContext& ctx) const \
-> decltype(ctx.out()) { \
return formatter<Base, Char>::format(static_cast<Base>(val), ctx); \
} \
}
FMT_FORMAT_AS(signed char, int);
FMT_FORMAT_AS(unsigned char, unsigned);
FMT_FORMAT_AS(short, int);
FMT_FORMAT_AS(unsigned short, unsigned);
FMT_FORMAT_AS(long, long long);
FMT_FORMAT_AS(unsigned long, unsigned long long);
FMT_FORMAT_AS(Char*, const Char*);
FMT_FORMAT_AS(std::basic_string<Char>, basic_string_view<Char>);
FMT_FORMAT_AS(std::nullptr_t, const void*);
FMT_FORMAT_AS(detail::std_string_view<Char>, basic_string_view<Char>);
template <typename Char> struct basic_runtime { basic_string_view<Char> str; };
/** A compile-time format string. */
template <typename Char, typename... Args> class basic_format_string {
private:
basic_string_view<Char> str_;
public:
template <typename S,
FMT_ENABLE_IF(
std::is_convertible<const S&, basic_string_view<Char>>::value)>
FMT_CONSTEVAL FMT_INLINE basic_format_string(const S& s) : str_(s) {
static_assert(
detail::count<
(std::is_base_of<detail::view, remove_reference_t<Args>>::value &&
std::is_reference<Args>::value)...>() == 0,
"passing views as lvalues is disallowed");
#ifdef FMT_HAS_CONSTEVAL
if constexpr (detail::count_named_args<Args...>() ==
detail::count_statically_named_args<Args...>()) {
using checker = detail::format_string_checker<Char, detail::error_handler,
remove_cvref_t<Args>...>;
detail::parse_format_string<true>(str_, checker(s, {}));
}
#else
detail::check_format_string<Args...>(s);
#endif
}
basic_format_string(basic_runtime<Char> r) : str_(r.str) {}
FMT_INLINE operator basic_string_view<Char>() const { return str_; }
};
#if FMT_GCC_VERSION && FMT_GCC_VERSION < 409
// Workaround broken conversion on older gcc.
template <typename...> using format_string = string_view;
inline auto runtime(string_view s) -> string_view { return s; }
#else
template <typename... Args>
using format_string = basic_format_string<char, type_identity_t<Args>...>;
/**
\rst
Creates a runtime format string.
**Example**::
// Check format string at runtime instead of compile-time.
fmt::print(fmt::runtime("{:d}"), "I am not a number");
\endrst
*/
inline auto runtime(string_view s) -> basic_runtime<char> { return {{s}}; }
#endif
FMT_API auto vformat(string_view fmt, format_args args) -> std::string;
/**
\rst
Formats ``args`` according to specifications in ``fmt`` and returns the result
as a string.
**Example**::
#include <fmt/core.h>
std::string message = fmt::format("The answer is {}.", 42);
\endrst
*/
template <typename... T>
FMT_NODISCARD FMT_INLINE auto format(format_string<T...> fmt, T&&... args)
-> std::string {
return vformat(fmt, fmt::make_format_args(args...));
}
/** Formats a string and writes the output to ``out``. */
template <typename OutputIt,
FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
auto vformat_to(OutputIt out, string_view fmt, format_args args) -> OutputIt {
using detail::get_buffer;
auto&& buf = get_buffer<char>(out);
detail::vformat_to(buf, fmt, args, {});
return detail::get_iterator(buf);
}
/**
\rst
Formats ``args`` according to specifications in ``fmt``, writes the result to
the output iterator ``out`` and returns the iterator past the end of the output
range. `format_to` does not append a terminating null character.
**Example**::
auto out = std::vector<char>();
fmt::format_to(std::back_inserter(out), "{}", 42);
\endrst
*/
template <typename OutputIt, typename... T,
FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
FMT_INLINE auto format_to(OutputIt out, format_string<T...> fmt, T&&... args)
-> OutputIt {
return vformat_to(out, fmt, fmt::make_format_args(args...));
}
template <typename OutputIt> struct format_to_n_result {
/** Iterator past the end of the output range. */
OutputIt out;
/** Total (not truncated) output size. */
size_t size;
};
template <typename OutputIt, typename... T,
FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
auto vformat_to_n(OutputIt out, size_t n, string_view fmt, format_args args)
-> format_to_n_result<OutputIt> {
using traits = detail::fixed_buffer_traits;
auto buf = detail::iterator_buffer<OutputIt, char, traits>(out, n);
detail::vformat_to(buf, fmt, args, {});
return {buf.out(), buf.count()};
}
/**
\rst
Formats ``args`` according to specifications in ``fmt``, writes up to ``n``
characters of the result to the output iterator ``out`` and returns the total
(not truncated) output size and the iterator past the end of the output range.
`format_to_n` does not append a terminating null character.
\endrst
*/
template <typename OutputIt, typename... T,
FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
FMT_INLINE auto format_to_n(OutputIt out, size_t n, format_string<T...> fmt,
T&&... args) -> format_to_n_result<OutputIt> {
return vformat_to_n(out, n, fmt, fmt::make_format_args(args...));
}
/** Returns the number of chars in the output of ``format(fmt, args...)``. */
template <typename... T>
FMT_NODISCARD FMT_INLINE auto formatted_size(format_string<T...> fmt,
T&&... args) -> size_t {
auto buf = detail::counting_buffer<>();
detail::vformat_to(buf, string_view(fmt), fmt::make_format_args(args...), {});
return buf.count();
}
FMT_API void vprint(string_view fmt, format_args args);
FMT_API void vprint(std::FILE* f, string_view fmt, format_args args);
/**
\rst
Formats ``args`` according to specifications in ``fmt`` and writes the output
to ``stdout``.
**Example**::
fmt::print("Elapsed time: {0:.2f} seconds", 1.23);
\endrst
*/
template <typename... T>
FMT_INLINE void print(format_string<T...> fmt, T&&... args) {
const auto& vargs = fmt::make_format_args(args...);
return detail::is_utf8() ? vprint(fmt, vargs)
: detail::vprint_mojibake(stdout, fmt, vargs);
}
/**
\rst
Formats ``args`` according to specifications in ``fmt`` and writes the
output to the file ``f``.
**Example**::
fmt::print(stderr, "Don't {}!", "panic");
\endrst
*/
template <typename... T>
FMT_INLINE void print(std::FILE* f, format_string<T...> fmt, T&&... args) {
const auto& vargs = fmt::make_format_args(args...);
return detail::is_utf8() ? vprint(f, fmt, vargs)
: detail::vprint_mojibake(f, fmt, vargs);
}
FMT_MODULE_EXPORT_END
FMT_GCC_PRAGMA("GCC pop_options")
FMT_END_NAMESPACE
#ifdef FMT_HEADER_ONLY
# include "format.h"
#endif
#endif // FMT_CORE_H_